25 May 2013

Training quote of the day #4: Euclid

Proclus (410-485) tells us that Ptolemy Soter, the first King of Egypt and the founder of the Alexandrian Museum, patronized the Museum by studying geometry there under Euclid. He found the subject difficult and one day asked his teacher if there weren't some easier way to learn the material. To this Euclid replied, "Oh King, in the real world there are two kinds of roads, roads for the common people to travel upon and roads reserved for the King to travel upon. In geometry there is no royal road."
(Source: library.thinkquest.org)

18 May 2013

Commentary - 2013 U.S. Championships, Round 9

In the last round (round 9) of the U.S. Championships, a number of games were worth examining closely for my training purposes.  The news link above includes the Robson-Kamsky game, which I don't look at here but which was fascinating to see during the live commentary. Kamsky again drew an unbalanced endgame after some complications, eventually winning the later playoff against Ramirez.

Game 1: GM Alejandro Ramirez - GM Larry Christiansen
This was an exciting contest in a Symmetrical English that Christiansen decided to unbalance with an early ...e5.  It was White's move 23 pawn sacrifice that really unbalanced the game, however, an excellent example of a sacrifice invigorating a position.  White breaks into Black's position starting on move 34 and some complex tactics ensue.  Winning this game put Ramirez into the playoff with Kamsky.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.12"] [Round "9.7"] [White "Ramirez, Alejandro"] [Black "Christiansen, Larry"] [Result "1-0"] [ECO "A37"] [WhiteElo "2551"] [BlackElo "2579"] [Annotator "ChessAdmin/Houdini"] [PlyCount "79"] [EventDate "2013.??.??"] [TimeControl "6000+890"] [WhiteClock "0:19:06"] [BlackClock "0:10:41"] 1. Nf3 c5 2. c4 Nc6 3. Nc3 e5 {Black is not usually this committal on move 3, preferring to develop with ...g6 and Bg7 or bringing out the other knight. Christiansen is indicating early that he is looking for an aggressive, unbalanced response and not a drawish line.} 4. g3 g6 5. Bg2 Bg7 6. a3 { this can be a prelude to a pawn sacrifice on b4, but this game continues in a more standard fashion, although the usual pawn push d3 is delayed.} Nge7 7. Rb1 (7. b4 {and now accepting the pawn can be extremely dangerous for Black, for example} cxb4 8. axb4 Nxb4 9. Ba3 Nec6 10. Nd5 e4 11. Nxb4 exf3 12. Bxf3 Nxb4 13. Bxb4 Bxa1 14. Qxa1 f6 15. Bd5 d6 16. O-O Kf8 17. Qa3 Kg7 18. Bxd6 Re8 19. e4 Bh3 20. Rb1 b6 21. d4 Qd7 22. e5 Qf5 23. Re1 fxe5 24. Bxe5+ Kh6 25. Be4 Qg4 26. Qe3+ g5 27. f3 Qd7 28. Bf6 Qf5 29. Be5 Qf7 30. g4 Rac8 31. Bd5 Qd7 32. Kf2 b5 33. Ra1 a5 34. Rxa5 Bxg4 35. h4 Qf5 36. Ra6+ Kh5 37. Bf7+ Kxh4 38. Rh6+ { 1-0 (38) Aguettaz,M (2443)-Tomazini,Z (2267) Pula 2012}) 7... O-O 8. O-O a5 9. Ne1 {part of the standard plan in this position, to reposition the knight with the idea of supporting the b4 advance.} d6 10. Nc2 a4 {as mentioned during the live commentary, the idea is to disrupt the b4 advance by taking en passant on b3, which would prevent White from recapturing with the a3 pawn as normal after an exchange on b4. White therefore continues by moving the knight on yet again.} 11. Ne3 Nd4 {the knight looks really strong here and White has no good way to get rid of it in the near term.} 12. d3 {usually this is played earlier, among other things to free up the Bc1, which is now blocked by the Ne3.} h6 { this guards against the typical Bg5 idea White has, with either an awkward pin on the Ne7 or provoking ...f6 as the result. Although it's a prophylactic move, I'm not sure it was truly necessary and perhaps Black could have done something more for his development.} 13. Re1 (13. Nxa4 {this pawn snatch doesn't tactically work, as also pointed out during the live commentary, due to a deflection tactic after} Nxe2+ 14. Qxe2 Rxa4) 13... Qa5 {after White's last move ...Nxe2 no longer tactically protects the a4 pawn, so Black has to defend it the old-fashioned way by moving a piece.} 14. Ned5 Nxd5 15. Bxd5 Kh7 {proactively moving off the diagonal with the pin on the f-pawn.} 16. Be3 { White would be fine with trading his bishop, which has little scope, for Black's finely posted knight.} Nb3 17. Ne4 Qb6 18. Nd2 f5 19. Nxb3 {White finally gets rid of the knight in his territory and saddles Black with defending the isolated b3 pawn.} axb3 20. Bd2 {White continues his piece maneuvers, getting out of the way of further Black pawn pushes and allowing his next move.} Bd7 21. e3 {concentrating on defending the key f4 square.} Rae8 22. Bc3 Re7 (22... f4 {would be premature here, for example} 23. exf4 exf4 24. Rxe8 Rxe8 25. Bxg7 Kxg7 26. Qf3 $14) 23. a4 {Houdini immediately finds this move and likes its dynamic possibilities. This was a key point in the game, as Ramirez's positional pawn sacrifice completely changes the dynamics of the game.} Bxa4 24. Ra1 Ra8 25. e4 {again both Ramirez and Houdini agree on the next aggressive blow, this time in the center.} f4 26. gxf4 exf4 27. Bxg7 Kxg7 28. Qf3 {see how this idea from the move 22 variation makes a reappearance. Black's pieces on the queenside are temporarily out of play, as pointed out during the live commentary, while White now has local superiority on the kingside for an attack.} Re5 29. Qxf4 Rf8 30. Qe3 Bc6 31. f4 Rh5 {this turns out to bit a bit awkward after White's next move.} (31... Ree8 $5) 32. Qg3 $14 Bxd5 33. exd5 Rhf5 {after this, White's rooks open up with heavy fire on Black's position.} (33... Qc7 {is Houdini's move and was also mentioned during the commentary. Black needs to get the queen back over for defense.}) 34. Re6 ( 34. Re7+ {was favored in the live commentary and is also Houdini's preference for continuing the attack. The idea is to force the rook on the 8th rank off before playing Ra8. In the game continuation, Black voluntarily does this, making things easier for White.} R8f7 (34... R5f7 35. f5 g5 36. Re6 Rf6 37. h4) 35. Re6 R5f6 36. Ra8) 34... R8f6 (34... R5f6) 35. Ra8 Rxe6 36. dxe6 Qc7 37. Re8 (37. Qh4 {was brought up during the live commentary as the strongest continuation.} g5 38. Qh5) 37... d5 {this loses immediately to the pawn push, although the tactic is not necessarily obvious.} (37... g5) 38. e7 Kf7 39. Rh8 Kxe7 40. Qxg6 {and now Black loses material, with his Rf5 under attack and the simultaneous White threat of skewering his king and queen along the 7th rank.} 1-0

Game 2: GM Timur Gareev - GM Conrad Holt
The opening phase saw Holt reject a possible early draw in an Exchange Slav and eventually end up in a closed position, but with some chances for both sides to try and make progress.  Choices made about where to play were worth studying, with Houdini for example suggesting White could have pursued a queenside strategy.  A long endgame struggle ends after a slip by Holt allows White to force a queen exchange that would give him a winning K+P endgame.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.12"] [Round "9.8"] [White "Gareev, Timur"] [Black "Holt, Conrad"] [Result "1-0"] [ECO "D13"] [WhiteElo "2674"] [BlackElo "2513"] [Annotator "ChessAdmin/Houdini"] [PlyCount "168"] [EventDate "2013.??.??"] [TimeControl "6000+1155"] [WhiteClock "0:02:16"] [BlackClock "0:00:34"] 1. d4 d5 2. c4 c6 3. cxd5 {the Exchange Slav, which has the reputation for being a very drawish opening. It can be, but usually only if both players are happy with a draw.} cxd5 4. Nf3 Nf6 5. Nc3 Nc6 {varying with ...a6 or ...Qb6 here would be one way to go for a more unbalanced position.} 6. Bf4 Nh5 { the classic treatment of the variation is to keep symmetry with ...Bf5. The text move in fact scores over 50 percent in the database.} 7. Bd2 {the usual choice, White chooses a safe path for the bishop, implicitly arguing that while the Bd2 isn't on a great square, the Nh5 is on a worse one.} e6 { indicating that Black is looking for an unbalanced game.} (7... Nf6 {is the drawing line, if Black is willing to accept that outcome. White is faced with the choice of continuing play with his bishop on d2, moving it to another substandard square, or repeating moves.}) 8. e3 Bd6 9. Ne5 g6 {only a handful of games are in the database, but this scores 70 percent for White. Weakening the dark-square complex like this looks strange, but White is not in a position to take advantage of it, with his relevant bishop locked in. It also allows the possibility of Nh5-g7-f5 at some point.} (9... Nf6 {is the other main choice, which scores better for Black overall, although not in the following high-level example, also a long endgame win fo White.} 10. f4 O-O 11. Bd3 Ne7 12. O-O b6 13. Be1 Bb7 14. Bh4 Ne4 15. Bxe4 dxe4 16. Qb3 Qe8 17. Bxe7 Qxe7 18. a4 Bb4 19. f5 f6 20. Ng4 Rac8 21. Rfc1 Rfe8 22. Nf2 a5 23. Rc2 Ba6 24. Qxe6+ Qxe6 25. fxe6 Rxe6 26. Rac1 Rec6 27. d5 R6c7 28. Rd1 f5 29. g4 g6 30. gxf5 gxf5 31. Nh3 Rg7+ 32. Rg2 Bc5 33. Rxg7+ Kxg7 34. Kf2 Kf6 35. Nf4 Bc4 36. Rg1 Bb4 37. h4 Bb3 38. Nfe2 Rd8 39. Nd4 Bxd5 40. Rg5 Be6 41. Rh5 Kg6 42. Nxe6 Rd2+ 43. Ke1 Rxb2 44. Nf4+ Kg7 45. Rg5+ Kf6 46. Nfd5+ Ke5 47. Nxb4 axb4 48. Ne2 Kd5 49. Rxf5+ Kc4 50. Rb5 Ra2 51. Rxb6 b3 52. Nd4 b2 53. Kd1 Ra3 54. Kd2 Ra2 55. Nc2 h5 56. a5 Rxa5 57. Rb4+ Kd5 58. Rxb2 Ke5 59. Nd4 Ra3 60. Rb5+ Kf6 61. Rxh5 Rd3+ 62. Ke2 Rxd4 63. exd4 {1-0 (63) Ivanchuk,V (2729)-Morozevich,A (2721) Monte Carlo 2006}) 10. Nb5 Be7 {Black needs to keep the bishop on the board to help cover the dark squares.} 11. Bd3 O-O 12. O-O a6 $11 {Black has apparently achieved what he intended, reaching equality out of the opening but in a relatively unbalanced position which may give him chances to pursue a win.} 13. Nc3 Bd6 {this appears to lose Black time and give White some initiative.} ( 13... Nxe5 {seems logical here, getting rid of the strong Ne5, which is an analagous theme in the Stonewall.}) 14. f4 {now exchanging on e5 would be favorable for White, giving him a cramping pawn on e5 and the half-open f-file. } Bd7 15. Qf3 (15. Na4 {is Houdini's choice here, with the idea of pursuing a queenside strategy and following up with Rc1.}) 15... Be8 (15... f5 {is another option, going for a Stonewall-like formation that would shut White down on the kingside.}) 16. Qh3 Ng7 17. Rf3 {an aggressive-looking move that goes nowhere for White and causes him to lose time repositioning the rook later.} (17. Rac1 $5) 17... f6 18. Ng4 h5 19. Nf2 f5 {this seems unnecessary, as the Be8 already covers g6 (why it was moved there in the first place, one would imagine).} (19... Rc8 $5 {immediately looks fine.}) 20. Bf1 Rc8 21. Rd1 { at this point we have a largely closed position with a lot of pieces clogging up the board. Both sides attempt to reposition themselves.} Rf7 (21... Bf7 { followed by Ng7-e8-f6 would bring the knight back into the game.}) 22. Nd3 Rfc7 {While the doubled rooks look good, it's unclear what they can accomplish on the c-file.} 23. Be1 Be7 24. Rf2 Bf7 {as happened earlier, Houdini again prefers a queenside strategy starting with Na4, looking to exploit the hole on b6.} 25. Ne5 (25. Na4 {as happened earlier, Houdini again prefers a queenside strategy starting with the text move, looking to exploit the hole on b6.}) 25... Nxe5 {now that the position is closed on the kingside, this is a more favorable exchange for Black.} 26. dxe5 Be8 27. Rfd2 Bd7 (27... g5 {is what the aggressive engine recommends. Black in fact has a structure similar to a Dutch Stonewall, with the potential for a well-supported pawn advance on the kingside.}) 28. Bd3 Qf8 (28... Bc5 {looks good, hitting the e3 pawn, but Black has different ideas in mind for his bishops.}) 29. Rc2 {inviting Black's next move.} Ba4 30. b3 Bb5 31. Qf3 Bb4 {this sets off a sequence of complex exchanges.} (31... Bxd3 32. Rxd3 b5 {followed by ...Bb4 gives Black a small plus here, according to Houdini.}) 32. Nxb5 Rxc2 33. Bxb4 Qxb4 34. Nd6 Kh7 35. h3 {neither side it seems wants to resolve the question of which Black rook will be taken.} Rc1 36. Nxc8 {finally!} Rxc8 {after the dust settles, Houdini considers the position as equal. With only the c-file open and more or less equivalent minor pieces, that seems reasonable.} 37. g4 hxg4 38. hxg4 {White has opened the h-file, which he perhaps has a better chance to exploit, as well as clearing some more light squares for his bishop.} Qa3 39. Qe2 Kg8 40. Kg2 Rc1 41. Rd2 Qc5 42. Rc2 {deciding to force the exchange.} Rxc2 43. Bxc2 { again, full equality.} Kf7 44. Kg3 d4 45. gxf5 gxf5 46. e4 d3 47. Qxd3 Qg1+ 48. Kf3 Qh1+ 49. Ke3 Qg1+ 50. Kd2 Qf2+ 51. Kd1 Qg1+ 52. Kd2 Qf2+ 53. Kc3 Qxf4 { a long dance to maintain equality.} 54. Qd7+ Kg8 55. Qc8+ Kh7 56. Qxb7 Qxe5+ 57. Kc4 Qb2 58. Bd3 Qc1+ 59. Kd4 Qg1+ 60. Kc3 Qa1+ 61. Kb4 a5+ 62. Kc5 (62. Kxa5 $2 Qc3+ {picks up the bishop.}) 62... e5 (62... Qc3+ {would have continued the dance.}) 63. Qd5 f4 {Black appears to be trying for a win - otherwise he could have continued the previous sequence of checks - but his queen is somewhat misplaced and his knight is out of the action, leaving White with good counterplay.} 64. Kd6 Qxa2 (64... f3 $5) 65. Bc4 Qa3+ 66. Kxe5 { Houdini considers this equal, but it looks a lot easier to play as White here.} Qe7+ {what should be the losing move, according to Houdini. White now picks up the f-pawn, but is subjected to a series of checks.} (66... f3) (66... Qf8) 67. Kxf4 Qh4+ 68. Ke3 Qe1+ 69. Kd4 (69. Kf3 {would eventually allow White's king to run to the queenside and block the checks, keeping the extra pawn.} Qh1+ 70. Kf2 Qh4+ 71. Ke2 Qg4+ 72. Kd2 Qf4+ 73. Kc2 Qf2+ 74. Kc3 Qe1+ 75. Qd2) 69... Qg1+ 70. Ke5 Qg3+ 71. Kf6 {now Black regains the pawn after another series of checks.} Qf4+ 72. Ke7 Qc7+ 73. Qd7 Qe5+ 74. Kf8 Qb8+ 75. Ke7 Qe5+ 76. Be6 Qxe4 $11 77. Qd5 Qb4+ (77... Qxd5 78. Bxd5 Nf5+ {is an excellent drawing idea. White cannot stop Black from eliminating his last pawn, for example} 79. Kd7 Nd4 80. Kd6 Nxb3) 78. Kf6 Qh4+ 79. Kf7 Qf4+ 80. Ke7 Qb4+ 81. Kd7 Nxe6 82. Kxe6 {Black, after playing a long and what must have been exhausting game, now lets it slip away quickly, showing how difficult queen endings can be.} Kh6 (82... Qe1+) 83. Kd7 {White screens himself from further checks, giving himself the initiative.} Kg7 {this now allows White to gang up with both king and queen on the Black king and then force an exchange of queens, with a winning K+P ending. } (83... a4 84. Qc6+ Kh5 85. bxa4 {looks good for White as well.}) 84. Qe5+ Kf7 {one continuation would be Qe6+, Kf8, Qe8+, Kg7 and then Qe7+} 1-0

Game 3: FM John Bryant - Yaacov Norowitz
The Caro-Kann Bronstein-Larsen variation finally chalks up a win in this event, as Norowitz masterfully uses Black's positional characteristics to his advantage, instead of having White take over the initiative as occurred in previous games.  It is both fitting and ironic that Black's doubled f-pawns are the key to final victory.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.12"] [Round "9.11"] [White "Bryant, John"] [Black "Norowitz, Yaacov"] [Result "0-1"] [ECO "B16"] [WhiteElo "2442"] [BlackElo "2451"] [Annotator "ChessAdmin/Houdini"] [PlyCount "78"] [EventDate "2013.??.??"] [TimeControl "6000+1385"] [WhiteClock "0:13:01"] [BlackClock "0:02:50"] 1. e4 c6 2. d4 d5 3. Nc3 dxe4 4. Nxe4 Nf6 5. Nxf6+ gxf6 {Norowitz is persistent, still playing the Bronstein-Larsen after losses with it in two previous rounds.} 6. Nf3 {not the most challenging continuation, as it invites Black to develop his bishop with a pin.} Bg4 7. Be2 e6 8. O-O Bd6 {instead of the ...Qc7 played in the first round against Christiansen.} 9. c4 Rg8 {a move that Norowitz never managed to get in during the round 1 game.} 10. Kh1 Nd7 11. d5 Qe7 {Norowitz now varies from Tringov-Smyslov (!), presented below as a fine example of an attacking game in this opening line.} (11... Nc5 12. Nd4 f5 13. Bxg4 Rxg4 14. h3 Qf6 15. Nf3 Rxc4 16. dxc6 Ne4 17. cxb7 Rb8 18. Qd3 Rb4 19. Be3 R4xb7 20. b3 Rd7 21. Qa6 Bc5 22. Bxc5 Nxc5 23. Qa5 Nd3 24. Kg1 Rbd8 25. Rab1 Kf8 26. Ne1 Ne5 27. f4 Ng6 28. Nf3 Kg7 29. g3 Rc8 30. Rbd1 Rdc7 31. Rd2 Qe7 32. Ne5 Rc5 33. Nxg6 hxg6 34. Qb4 Qf6 35. Re1 a5 36. Qa3 Rc3 37. Kh2 Rxg3 38. Qxa5 Qh4 {0-1 (38) Tringov,G-Smyslov,V Havana 1965}) 12. dxc6 bxc6 13. Nd4 Bxe2 14. Qxe2 {White has exchanged off another pair of minor pieces, a good strategic move that brings him closer to the endgame.} Rc8 15. Qh5 {White decides to go pawn hunting, which does not turn out well for him.} (15. Be3 { seems solid.}) 15... f5 {a key move idea in this variation (also played earlier on in the Smyslov game given above). The diagonal is opened up for Black's queen and the doubled pawn is used to grab space in White's territory.} 16. Qxh7 Nf6 {Black uses the pawn sacrifice to activate his pieces, moving his knight into the game and also making the Bd6 a much more powerful piece with the h-file now open for attacking purposes (targeting the h2 pawn).} 17. Qh3 Ng4 18. g3 {this cuts off the Black bishop, but causes additional problems for White.} (18. f3 Nxh2 19. Re1 Nf1 {is a wild line, in which Black is OK because of the latent threat of a pin on the h-file, for example} 20. Rxf1 $2 (20. Nxf5 Ng3+ 21. Nxg3 Bxg3 22. Re2 $11) 20... Qf6 $19) (18. Nf3 {may be a more solid defense.}) 18... Bc5 $15 19. f3 Bxd4 20. fxg4 Rxg4 {Black has now regained his sacrificed pawn and his pieces are certainly more active and better placed, although the position is still quite sharp.} 21. Qg2 Qb4 22. Bf4 {now White chooses to sacrifice the c-pawn, but his compensation is not as robust as Black's was earlier.} (22. Qc2 $5) 22... Qxc4 23. Rfd1 e5 $17 {now Black gets rolling in the center and the strength of this passed pawn proves to be the deciding factor in the end.} 24. Rac1 Qe6 25. Re1 f6 {a remarkable display of how Black's normally weak pawn grouping can become a strength.} 26. Be3 Kf7 27. Bxd4 Rxd4 28. Rf1 Kg6 {a bold and effective use of the king. Ironically White's two kingside pawns serve as effective shields for Black's king.} (28... e4 {was also possible.}) 29. Rc2 Rcd8 {Black's domination of the central squares and files is now complete.} 30. h4 (30. Rxc6 Qxa2 31. h4 Rd1 $19) 30... Rd1 31. Rxd1 Rxd1+ 32. Kh2 Qd5 $19 33. Rf2 (33. Qxd5 cxd5 {and Black's central pawns will be unstoppable.}) 33... Qxg2+ {Black prefers to trade queens here and head into the less complicated rook ending.} 34. Kxg2 $17 Rd4 (34... c5 $5) 35. Rc2 f4 36. g4 (36. Rxc6 $2 {would be bad due to} Rd2+ {and now White loses the g-pawn in all variations, for example} 37. Kh3 Rd3 38. Kh2 Rxg3) (36. gxf4 Rxf4 37. Kg3 {might be a more stubborn defense.}) 36... Rd3 $19 {Black's rook dominates White's back ranks and can enable the Black pawns to roll forward.} 37. Kh2 Rg3 38. Rg2 Rxg2+ 39. Kxg2 e4 {now Black's extra f-pawn ensures his victory, a fitting end for a Bronstein-Larsen game!} 0-1

Game 4: GM Melik Khachiyan - GM Marc Arnold
For Slav devotees, this game is an excellent illustration of why almost no one plays a fianchetto against it.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.12"] [Round "9.14"] [White "Khachiyan, Melik"] [Black "Arnold, Marc"] [Result "1/2-1/2"] [ECO "D11"] [WhiteElo "2518"] [BlackElo "2538"] [Annotator "ChessAdmin/Houdini"] [PlyCount "36"] [EventDate "2013.??.??"] [TimeControl "6000+1130"] [WhiteClock "0:26:00"] [BlackClock "0:18:49"] 1. Nf3 d5 2. d4 Nf6 3. g3 {an uncommon continuation with some transpositional possibilities.} c6 {Black chooses a Slav setup, which immediately aims to nullify White's pending bishop development to g2.} 4. Bg2 Bf5 5. O-O Nbd7 6. c4 {we now have a fianchetto-type Slav, which is not nearly as effective an opening for White as the analagous Catalan against the QGD (without ...c6 being played)} e6 7. Qb3 {an aggressive move, but one which scores over 56 percent for Black in the database. All of the main continuations favor Black, showing how the fianchetto line versus the Slav is generally ineffective.} Qc8 {a rather passive development for the queen.} (7... Qb6 {is the most popular and should be the easiest road to equality. Exchanging queens on b6 would be fine for Black, as he then would get the half-open a-file and the doubled b-pawns are not in fact weak.}) 8. Nc3 dxc4 {a novelty in the database. Black normally continues to maintain the tension in the center and have the extra control over e4. The text move leads to a looser continuation by Black which is more aggressive and unbalanced.} (8... h6 {is the most played here.}) 9. Qxc4 b5 10. Qb3 b4 {the logical follow-up. Now that Black has chosen this aggressive line which also weakens his queenside, he needs to keep hitting White's pieces to disrupt his opponent and keep him off-balance.} 11. Na4 (11. Nb1 {is an alternative, looking to reposition the knight to d2.}) 11... Be4 12. Bd2 {White plays carefully to neutralize Black's chances.} (12. Bg5 $5 Bd5 13. Qd3 Be4 14. Qe3 {would see White play for an advantage and avoid the repetition line from the game.}) 12... Bd5 13. Qc2 Qa6 {by attacking the Na4 and the e2 pawn simultaneously, Black sets up the conditions for the repetition. The White queen must stay on the d1-a4 diagonal to protect the knight and White also has to worry about the pawn.} 14. Rfe1 Be4 15. Qb3 { White accepts the idea of a draw by repetition.} (15. Qd1 {would avoid this, but the position is equal in any case.}) 15... Bd5 16. Qc2 Be4 17. Qb3 Bd5 18. Qc2 Be4 1/2-1/2

12 May 2013

Commentary - 2013 U.S. Championships, Round 8

The most interesting games of round 8 for me were on the two top boards, where Kamsky-Gareev saw some wild swings and an eventual forced repetition by Black, while Abrahamyan-Krush was a full-on clash in a Taimanov Sicilian.  The games and comments can be found at the above link.

The most relevant game again for my studies was a Caro-Kann, the third (!) time the Bronstein-Larsen variation has appeared at the championships.  This time it was Alexander Stripunsky who essayed it as Black against Robert Hess, however, not Yaacov Norowitz.  Alas, Black again went down to defeat after failing to generate any kingside attack or meaningful counterplay.  In none of the games has Black seemed to want to be as aggressive as the opening demands; in this game, for example, he could have played the early 6...h5!? which in fact scores quite well.

Live coverage of round 9 is ongoing and it looks like Gata Kamsky may be trying to bait Ray Robson into a premature attack against his unusual, somewhat passive-looking Sicilian Kan variation.  A Kamsky win would give him clear first place. Meanwhile, Irina Krush as White only needs to draw against Camilla Baginskaite in order to ensure her title victory in the women's championship.

[Event "US Chess Championships"] [Site "Saint Louis USA"] [Date "2013.05.11"] [Round "8"] [White "Robert Hess"] [Black "Alexander Stripunsky"] [Result "1-0"] [ECO "B16"] [WhiteElo "2595"] [BlackElo "2570"] [Annotator "ChessAdmin/Houdini"] [PlyCount "71"] [EventDate "2013.05.03"] 1. e4 c6 2. d4 d5 3. Nc3 dxe4 4. Nxe4 Nf6 5. Nxf6+ gxf6 {the Bronstein-Larsen makes its third appearance in the championships.} 6. g3 {Hess avoids the main line with c3, as the other White players have done in this tournament. Here he chooses to immediately fianchettoes his bishop. While this is a main idea in the c3 line, the early fianchetto is rarely played.} Nd7 {has not been played before in the database. This seems like a slow way to develop.} (6... h5 { actually scores over 60 percent for Black. Kingside aggression is the key to success in this variation.}) 7. Bg2 Nb6 {an early commitment of the knight to this square, but Black now needs to get it out of the way of his bishop and queen.} 8. b3 {White focuses on pawn moves rather than piece development.} (8. Nf3 $5) 8... Bf5 (8... h5 {is what Houdini likes here, but Black evidently doesn't feel aggressive enough.}) 9. c4 Qd7 10. a4 Rd8 {with White's queenside pawns already looking menacing, Black decides not to castle long.} 11. a5 Nc8 12. a6 $14 b6 {Despite White's lack of piece development to this point, his bishops have great prospects and has a potentially better king position, while Black's king is not so comfortable.} 13. Ne2 Bh3 14. Bxh3 Qxh3 15. Nf4 Qd7 16. O-O $16 {Black's sole attacking idea on the kingside, exchanging on Bg2, has been neutralized by White, who now also has a significantly safer king.} Bg7 ( 16... Qxd4 $6 17. Qf3 {threatens c6 and gives White major attacking prospects.} Bg7 (17... Qxa1 $2 18. Qxc6+ Rd7 19. Qxc8+ Rd8 20. Qc6+ Rd7 21. Rd1) 18. Ba3) 17. Qf3 O-O {while not a poor move in this situation, it's a bad strategic sign for Black, who was not able to use the g-file for anything and now is saddled with permanent positional flaws.} 18. d5 cxd5 19. Nxd5 f5 20. Ra2 { White keeps his options open for the rook.} e6 21. Nb4 Qd4 {it appears like Black is lashing out desperately, hoping for counterplay.} (21... Qe8 {is Houdini's suggestion, which is more passive and defensive in nature.}) 22. Qb7 Qc3 23. Nc6 {White's pieces are simply dominant at this point.} Rd3 24. Ra3 { White now safely neutralizes Black's attack.} Bd4 25. b4 Qxc4 26. Rxd3 Qxd3 27. Nxd4 Qxd4 28. Bh6 {although now a pawn down, this is meaningless, as White's pieces still thoroughly dominate the board.} Rd8 29. Rc1 Nd6 30. Qxa7 Ne4 31. Be3 Qxb4 32. Qxb6 Qxb6 33. Bxb6 {the win now takes shape.} Ra8 34. a7 Nf6 ( 34... Nd6 {would be more stubborn, according to Houdini.}) 35. Bd4 Nd5 36. Rb1 {and Black cannot stop Rb8} 1-0

11 May 2013

Commentary - 2013 U.S. Championships, Round 7

In round 7, I found two games to be of particular interest for study purposes.  In the first, Irina Krush resumes her winning ways, this time in a war of maneuver with Viktorija Ni in a Nimzo-English.  Irina does not have an easy way to the win, however, missing an interesting tactic on move 29 and allowing Black for a while to have a small advantage.  In the second, I give props to Yaacov Norowitz for bringing out the aggressive, unbalanced Bronstein-Larsen variation of the Caro-Kann again after losing to Larry Christiansen in round 1.  Facing Sam Shankland, Norowitz varies from his previous effort on move 8 with an improvement, but after exchanging bishop for knight on f3, Black's initiative peters out on the kingside.  In this variation of the Caro-Kann, if Black has no counterplay on the kingside, White normally enjoys the advantage of a free attacking hand on the queenside, which is exactly what happens here.

At the time of posting, live coverage of round 8 (the penultimate one) is underway.  The leader on the women's side, Krush playing Black in a Taimanov Sicilian, looks like she has a significant advantage over Tatev Abrahamyan.  Meanwhile, open championship leader Gata Kamsky is having some difficulty as White against Timur Gareev.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.10"] [Round "7.4"] [White "Krush, Irina"] [Black "Ni, Viktorija"] [Result "1-0"] [ECO "A17"] [WhiteElo "2470"] [BlackElo "2262"] [Annotator "ChessAdmin/Houdini"] [PlyCount "81"] [EventDate "2013.??.??"] [TimeControl "6000+950"] [WhiteClock "0:27:53"] [BlackClock "0:30:35"] 1. Nf3 Nf6 2. c4 e6 3. Nc3 {instead of playing d4 and heading for a standard queen pawn opening, White switches to an English continuation.} Bb4 {the Nimzo-English.} 4. Qc2 {unlike the Nimzo-Indian, where the text move is merely one option among several major lines, White overwhelmingly chooses Qc2 (and sometimes Qb3) in the English, to preserve his pawn structure after Bxc3; g3 is the one popular alternative to this approach.} O-O 5. a3 Bxc3 {otherwise the bishop move has simply been a loss of time.} 6. Qxc3 b6 7. e3 Bb7 8. b3 { White has a choice in this line between playing b3 or b4; one or the other will be necessary to develop with Bb2. The text move is the more solid way to play, with b4 grabbing a little more space.} d6 9. Bb2 Nbd7 10. Be2 Nc5 { one of the differences between this line and the b4 line is that Black has c5 available for the knight, even if only temporarily.} 11. d4 Nce4 {the e4 square is normally key in the Nimzo and Black takes advantage of her dominance of it.} 12. Qc2 c5 {challenging White's pawn center.} 13. O-O {White wisely chooses to remove her king before initiating action in the center.} Rc8 { the opening phase is over and both sides need to come up with their middlegame plans here.} 14. Rad1 {White's choice of which rook to move indicates that she is more interested in central and kingside play than in the queenside.} Qe7 15. dxc5 Rxc5 {this is a somewhat unusual choice for recapturing, but Black apparently wanted to avoid the below variation. The rook move perhaps would be better justified if Black could swing her rook over to the kingside.} (15... Nxc5 {and now} 16. Bxf6 gxf6 (16... Qxf6 17. Rxd6) 17. Nd2 f5 {is evaluated as equal by Houdini. Human players would of course dislike to see their pawn structure compromised, but in this case it doesn't seem like White can successfully exploit the holes on the kingside.}) 16. b4 (16. Nd2 {is Houdini's preference, with the aim of getting rid of the Ne4.}) 16... Rcc8 17. Qb3 {with tactical threats nonexistent, the middlegame enters a maneuvering phase. This is similar to what normally occurs in the Hedgehog and the position shares some characteristics of that.} Rfd8 18. Bd4 {this move seems largely designed to provoke Black's response.} e5 19. Bb2 {the d6/e5 pawn formation is now weaker and less flexible than the d6/e6 pawn center, especially with the backwards d6 pawn on the half-open file. It is currently well-guarded, but in the long run that could be a weakness. The e5 advance more importantly for the shorter term also creates a hole on d5 which White, if she can, will try to exploit.} Qe6 {Black recognizes the weakness of d5 and moves to reassert control over it, also putting the queen in an excellent central location on the a2-g8 and h3-c8 diagonals.} 20. Rc1 b5 {attempting to force the issue of the fate of the queenside pawns, taking advantage of the pin against the Qb3.} 21. Qd3 {the only good response.} bxc4 22. Rxc4 Bd5 { further exchanges on c4 are not in Black's interest, as her structural weakness at d6 would become much more evident with fewer pieces on the board.} 23. Rcc1 (23. Rxc8 Rxc8 24. Rc1 Rxc1+ 25. Bxc1 {would be an alternate way to play, but without the rooks on the board White does not have a good way to take advantage of the open c-file or increase pressure down the d-file.}) 23... Rb8 24. Qa6 {While the position is still equal, White starts to pick up a slight initiative by making threats Black needs to respond to. The 2-to-1 majority on the queenside and the open c-file are things White can use to try for an eventual advantage, as well as the half-open d-file.} Rb7 25. h3 { apparently intended to prevent ...Ng4 before moving the rook, but Houdini points out a tactical way for White to refute that.} (25. Rfd1 Ng4 26. Rxd5 { not an obvious move} Qxd5 27. Bc4 {and rather surprisingly the queen has no squares.}) 25... Qe7 {Black starts to face difficulties in an increasingly complex and tactical position. Here she retreats her queen to a much less active square.} (25... Rdb8 {is Houdini's suggestion as an alternate method of overprotecting the Rb7, necessary to allow the Bd5 mobility.}) 26. Rfd1 { it's worth observing how White's rooks and other pieces are working together and are well-placed to apply further pressure, while Black's more scattered and less cohesive pieces that are more oriented towards defense.} Bb3 {Houdini flags this as Black's first major error, given the tactic available on move 29. } (26... Rbd7) 27. Rd3 Rb6 28. Qa5 Be6 29. Nd2 (29. Bxe5 {is the tactic Houdini finds, based on a discovered back-rank mate threat.} dxe5 $2 30. Qxa7 { and White is going to pick up one of Black's rooks, for example} Nd7 31. Rxd7 Bxd7 32. Qxb6 $18) 29... h6 {Black now avoids future back-rank problems.} 30. Nf1 (30. Bf3 {would be an immediate way to fight for the e4 square.}) 30... Ne8 31. f3 Nc5 32. bxc5 (32. Rxc5 {is the capture preferred by Houdini, made possible by a pin tactic against the Rb6.} dxc5 33. Rxd8 Qxd8 34. bxc5 Rb8 35. Qxd8 Rxd8) 32... Rxb2 33. Nd2 {now White's pieces are looking rather uncoordinated, especially by comparison to the position on move 26. Houdini awards Black a slight plus here. Black has the open b-file and White's c5 pawn is isolated and weak.} Rdb8 $6 {this lets White off the hook in the center and drops the e5 pawn for insufficient compensation.} (33... Rc8 $15 {seems good for Black, immediately targeting the c-pawn, which is pinned to the hanging Rc1.}) 34. cxd6 Nxd6 35. Qxe5 R8b6 36. Bf1 {White extricates her bishop from the pin on the second rank.} R2b5 37. Qc3 {White has improved her piece placement by reorganizing over the last few moves and Black has no obvious counterplay.} Qg5 {this allows White to complete her consolidation and achieve a winnin position.} (37... Rb2) 38. Rxd6 Rxd6 39. Ne4 Qd5 $2 {this just drops a rook.} (39... Rb3 $16) 40. Bxb5 Rb6 41. Bc4 1-0

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.10"] [Round "7.8"] [White "Shankland, Sam"] [Black "Norowitz, Yaacov"] [Result "1-0"] [ECO "B16"] [WhiteElo "2612"] [BlackElo "2451"] [Annotator "ChessAdmin/Houdini"] [PlyCount "83"] [EventDate "2013.??.??"] [TimeControl "6000+1390"] [WhiteClock "0:35:56"] [BlackClock "0:29:54"] 1. e4 c6 2. d4 d5 3. Nd2 {this move is of course interchangeable with the more usual Nc3 given Black's response here. The only independent significance it has is if Black likes to play the offbeat 3...g6 in the main line Caro Kann, in which case White then has the pawn push c3 in response.} dxe4 4. Nxe4 Nf6 5. Nxf6+ gxf6 {venturing the Bronstein-Larsen variation again, as in round 1.} 6. Nf3 Bg4 7. Be2 e6 8. O-O Rg8 {Black still insists on avoiding the main choice . ..Bd6, but declines to repeat the choice he made in round 1 of ...Qc7. The text move has the advantage of being more immediately aggressive.} 9. Bf4 Bd6 10. Bg3 {this is Houdini's preference and a novelty, based on my database.} Bxf3 {this seems a little premature. White's bishop on f3 is also a very useful addition to his kingside defenders.} (10... Bxg3 11. hxg3 Nd7 $11) 11. Bxf3 $14 {Houdini awards White a slight plus here. White has no significant structural problems and is ahead in development.} f5 12. Qd2 Bxg3 13. hxg3 { this would be a weakening move if Black could take advantage of an attack down the h-file, but this doesn't materialize.} Nd7 14. Rfe1 Qc7 15. d5 {White decides to immediately attempt to seize the initiative, although a preparatory move might have been in order.} (15. c4) (15. Rad1) 15... cxd5 16. Qxd5 O-O-O 17. Qb3 Kb8 {Black has staved off White's immediate threats, but White will now have a much easier time attacking Black's king than vice versa.} 18. a4 Nc5 (18... Qb6 $5) 19. Qe3 {White does well to move his queen away from potential threats to exchange it, placing it on a square that influences the attack on the king via the g1-a7 diagonal while also eyeing Black's weak kingside.} Rc8 20. a5 $16 {this takes away the b6 square from black, cramping his defense. Black is under major pressure and has no counterplay.} Rgd8 21. Ra3 (21. b4 $5) 21... a6 22. Rc3 {the game is now increasingly tactical due to White's bringing more pieces into the attack.} Qe7 (22... Qxa5 {does not work because of} 23. Qf4+ Ka7 (23... Qc7 24. Rxc5 Qxf4 25. Rxc8+ Rxc8 26. gxf4) 24. b4) 23. Qf4+ Qd6 24. Re5 {White brings his other rook into the attack.} Ne4 {forced.} ( 24... Ka7 25. Rexc5 Qxf4 (25... Rxc5 26. Qxd6) 26. gxf4 Rxc5 27. Rxc5) 25. Rd3 Qc7 26. Bxe4 fxe4 27. Rxe4 Rxd3 28. cxd3 Qxf4 29. Rxf4 {White has cashed in his attack for an extra pawn, but the win is not clear in the ensuing rook endgame.} f5 30. f3 Rd8 31. Rh4 Rxd3 32. Rxh7 Rb3 33. g4 fxg4 34. fxg4 Ka7 { Houdini flags this as the losing move.} (34... Rb5) 35. Rh3 (35. g5 Rg3 36. Rg7 Rg4 37. Kf2 {and White will be able to chase the Black rook away.}) 35... Rxb2 36. g5 Rc2 37. g6 Rc8 38. Rf3 Rg8 39. Rf6 Kb8 40. Rxe6 Kc7 41. Kf2 Rf8+ 42. Kg3 {the king can now march up the board and will eventually force the Black rook away.} 1-0

Commentary - 2013 U.S. Championships, Round 6

In round 6 the last perfect score in the championships dropped, as the women's leader Irina Krush was held to a draw as Black by Sabina Foisor.  For me the most relevant game was Baginskaite-Zatonskih, another Modern Stonewall reached via the Slav move-order along the lines of Zatonskih's round 2 game.

In this game, Baginskaite seems better prepared in general against the Stonewall and must have had some expectation that Zatonskih would go into this line again.  Black nevertheless equalizes easily and holds at least some initiative throughout the game, although White manages to cleverly avoid some lurking Black threats in the early middlegame.  The inflection point of the game occurs on move 26 after a lengthy tactical sequence, where Black reveals a back-rank mate threat that prevents a White pawn recapture and gives her a lasting material advantage.  Black's road to the victory is still quite difficult, however, and White for a long time succeeds in placing various obstacles in her opponent's way.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.09"] [Round "6.16"] [White "Baginskaite, Camilla"] [Black "Zatonskih, Anna"] [Result "0-1"] [ECO "A84"] [WhiteElo "2278"] [BlackElo "2466"] [Annotator "ChessAdmin/Houdini"] [PlyCount "156"] [EventDate "2013.??.??"] [TimeControl "6000+1285"] [WhiteClock "0:01:40"] [BlackClock "0:02:34"] 1. d4 d5 2. c4 c6 3. Nf3 e6 4. e3 f5 5. Bd3 Nf6 6. O-O Bd6 7. b3 {Unlike in the round 2 game, White goes for a more standard plan against the Stonewall. The text move prepares Ba3 and an exchange of the Bd6, which would leave Black with a weak dark-square complex. Black's next move is designed to prevent this. } Qe7 8. Qc2 O-O 9. Ne5 {there is a wide variety of moves played here, but occupying e5 with a knight is a standard idea for White.} b6 10. Bb2 {a reasonable move but a new one nonetheless, according to the database.} Bb7 { this development of the light-square bishop is a feature of the Modern Stonewall and is now more popular than the old transfer of the bishop to h5. On b7, the bishop appears buried, but serves a useful function supporting the c-pawn and can spring to life if it advances and pawn exchanges occur in the center.} 11. cxd5 Nxd5 12. a3 Nd7 13. Nd2 Rac8 14. Ndc4 Bb8 {Houdini favors this retreat, which preserves the valuable bishop.} 15. Qe2 c5 {now the Bb7 looks quite strong.} 16. Nxd7 {exchanging the nicely posted Ne5 for the Nd7 seems counterintuitive, but is in fact a common idea in the Stonewall, in part because White can reposition her other knight to e5 later on. White starts to have problems in this position if this does not occur, as examined in the following sample variation. Black has a number of tactical possibilities lurking, with ideas including using her Nd5 for forks on c3 or f4, along with the two powerful bishops pointed at White's king.} (16. Rad1 cxd4 17. Bxd4 { recapturing with the e-pawn would allow ...Nf4, attacking the Qe2 and g2 simultaneously.} Nxe5 18. Nxe5 Nc3 19. Bxc3 Rxc3 20. f4 Bd5 (20... Rxb3 $2 21. Bc4) 21. b4 Bb3 $17) 16... Qxd7 17. dxc5 Rxc5 (17... Qc6 {is an interesting idea.} 18. f3 (18. cxb6 $2 Nf4 19. Qf3 Qxf3 20. gxf3 Nxd3) 18... Qxc5) 18. Rac1 Rd8 19. Rfd1 {White has avoided Black's nastier ideas through her earlier exchanges and is in a better position to fight for the center and d- and c-files. The position is evaluated as equal by Houdini.} Rcc8 20. Ne5 Qe7 { Black chooses to maintain her longer-term chances rather than exchange off the new Ne5.} (20... Bxe5 {would start a long, largely forced line leading to an equal endgame.} 21. Bxe5 Rxc1 22. Rxc1 Nxe3 23. Rc7 Qxd3 24. Rxg7+ Kf8 25. Qxd3 Rxd3 26. fxe3 Bd5 $11) 21. Ba6 {the key error, according to Houdini. Perhaps White did not see Black's move 24 or, more likely, the back-rank threat revealed on move 26. White needs to avoid the deflection tactic that gains Black the a-pawn.} (21. Rxc8 Rxc8 22. Nf3) (21. b4) 21... Rxc1 22. Rxc1 Bxe5 23. Bxe5 Qxa3 24. Ra1 Bxa6 25. Qxa6 Qxa6 26. Rxa6 Nb4 {White's back-rank weakness, exposed by Black's last move, prevents her from taking Black's a-pawn.} 27. Ra1 Rd3 28. Kf1 Nc6 29. Bc7 Rd7 (29... Rxb3 {was likely avoided by Black due to the extra activity it allows White's pieces. Houdini evaluates both this variation and the text move equally. It might have been easier for Black to simply take the material, however.} 30. Rc1 Ne7 31. Be5 Rb5 32. f4 Nd5 $17) 30. Bg3 Kf7 31. Rc1 Nb4 32. Ke2 e5 33. f3 (33. Bxe5 $2 Nd3) 33... Ke6 34. Rc8 Nd5 35. Re8+ Re7 36. Rc8 f4 {White's rook cannot make any meaningful threats, so Black decides to make some progress on the kingside.} 37. Bf2 Kd7 38. Ra8 Kc6 {Black is transferring her king to the main theater of action on the queenside, where it is needed to support an eventual pawn advance.} 39. e4 Nb4 40. Be1 Kb5 41. Bc3 Nc6 42. Kd3 Kc5 43. Rc8 Rd7+ 44. Kc2 {White has been doing well in placing obstacles in front of Black's queenside advance.} Kd6 45. b4 b5 {necessary to fix the b4 pawn in place. Black will now aim to force through ...a5 in the long run.} 46. Kb3 Rb7 47. Rh8 h6 48. Rc8 Rc7 49. Rg8 { exchanging rooks would leave White with simpler problems to solve in the endgame.} Ke6 50. Re8+ Re7 51. Rc8 Kd7 52. Rg8 Kc7 53. Rf8 Kb6 54. Ra8 Kb7 { both sides continue to focus on the queenside struggle. After the text move, Houdini considers the position equal.} (54... Re6 {is pointed out by Houdini, which would go after White's abandoned kingside pawns after the follow-up ... Rg6.} 55. g3 fxg3 56. hxg3 Rg6 57. g4 Rf6 58. Rg8 Rxf3 59. Kc2 $17 (59. Rxg7 $2 Nxb4 60. Rg6+ Kc5 61. Re6 Nc6 62. Kb2 Rf2+ 63. Kb1 Rf4 $19)) 55. Rf8 $11 Kc7 ( 55... Re6 {no longer works due to} 56. Rf7+) 56. Rg8 Kd7 57. Rf8 Kd6 58. Rg8 Rb7 59. Rc8 a5 {Black decides to stop dancing around with the rooks and force the issue.} 60. bxa5 b4 61. a6 Rb6 62. Bd2 {allows Black to make progress.} ( 62. Bb2 {would add another blockader to the b-file.}) 62... Rxa6 {now White faces an uphill battle, being down material and with Black's rook dominant on the a-file.} 63. Rg8 Ra3+ 64. Kc4 Ra2 65. Bxb4+ Nxb4 66. Kxb4 Rxg2 {classic endgame strategy, liquidate in one area in order to transfer your advantage to another.} 67. Kc4 h5 68. h4 Rg3 69. Rd8+ Ke6 70. Re8+ Kd6 71. Rd8+ Ke7 72. Rh8 (72. Rb8 Rxf3 73. Kd5 {is still difficult for White, but her king is better positioned.}) 72... Rxf3 73. Rxh5 Kd6 {now White can do little to stop Black from cleaning up.} 74. Rg5 Rg3 75. Rf5 Re3 76. Rf7 Rxe4+ 77. Kd3 Re3+ 78. Kd2 Rg3 0-1

10 May 2013

Training quote of the day #3: Old English Proverb

Old age and cunning will overcome youth and skill.
-- Old English proverb

Commentary - 2013 U.S. Championships, Round 5

As quoted in the Round 5 news report, GM Alejandro Ramirez had this to say about the following game.
"Shankland is known as a very booked-up player,” Ramirez said. “So I wanted to get him out of theory as soon as possible.” Ramirez said he knew the plan was working when they were both spending five minutes on every move.
I found the opening to be very interesting, a Nimzo-Larsen Attack against a Sicilian-style setup, which is not the most challenging way to oppose White's ideas.  Ramirez, who is blazing his way through the tournament so far, shows he is capable of analyzing unusual positions and thinking for himself while playing aggressively.

The other major news in Round 5 was that Gata Kamsky was (finally) held to a draw by Joel Benjamin, while Irina Krush continued her winning streak and was 5-0.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.07"] [Round "5.5"] [White "Ramirez, Alejandro"] [Black "Shankland, Sam"] [Result "1-0"] [ECO "A04"] [WhiteElo "2551"] [BlackElo "2612"] [Annotator "ChessAdmin/Houdini"] [PlyCount "67"] [EventDate "2013.??.??"] [TimeControl "6000+1145"] [WhiteClock "0:14:48"] [BlackClock "0:08:44"] 1. Nf3 c5 2. b3 {the Nimzo-Larsen.} d6 3. c4 g6 (3... e5 {is actually the main idea behind the previous move, but Black continues with his Sicilian-style development.}) 4. d4 Bg7 5. e3 Nc6 6. Bb2 Bg4 {breaking from the standard Sicilian ideas. This move in fact scores quite well for Black, at around 77 percent, but there are only a handful of games in the database with this position and only one at the professional level.} 7. Be2 cxd4 8. Nxd4 Bxe2 9. Qxe2 Nxd4 10. Bxd4 Bxd4 {a key decision to exchange, which seems slightly better for White, who unlike Black is not left with a kingside dark square weakness as a result. White's development is also a little easier. Also possible was playing to keep the dark-square bishops on the board.} (10... Qa5+ 11. Nd2 Nf6 12. O-O O-O $11) 11. exd4 d5 {Black is slightly behind in development and this does nothing to rectify that.} 12. c5 $14 {without the opposing bishop to challenge it, White's d4 pawn is a source of positional strength.} Nh6 13. Nd2 Nf5 14. O-O O-O 15. Nf3 b6 {challenging the head of the pawn chain, another strategic decision which seems to work out a little better for White.} 16. b4 bxc5 17. dxc5 {White deliberately goes for the option creating a greater imbalance in the position, rather than the more solid bxc5.} Re8 18. Rad1 e5 19. Rfe1 f6 20. Qa6 {a strong move, switching the queen to an area where she can exercise greater dominance and directly assist the pawn advance.} d4 {Black attempts to set his own pawns in motion and obtain counterplay. However, it's interesting to observe that while White has three pieces lined up in front of Black's pawns to oppose their advance, Black has none in front of White's.} 21. Nd2 Kg7 22. Ne4 {the knight has multiple functions here, obviously blockading e4 but also threatening to hop into d6 and offering support to the c5 pawn.} Rf8 23. c6 {White obviously believes the dictum that passed pawns must be pushed.} Nh4 {according to Houdini, the major turning point in the game, which is now evaluated as heavily in White's favor. Black apparently intended to play f5 as a followup, but that never actually happens. White's c-pawn is far enough advanced that it becomes a major force and Black must focus on restraining its progress, as his passed d-pawn is not nearly as threatening.} (23... Qc7 {seems like the best option, blockading the pawn.} 24. Rc1 Rab8 {preventing White's queen from going to b7} 25. b5 $14) 24. Rc1 $18 Qd5 (24... Qc7 {no longer works due to} 25. Qb7 Qxb7 26. cxb7 Rab8 27. Rc7+ Rf7 28. Rxf7+ Kxf7 29. Rc1 {and the well-placed Ne4 tactically protects the b7 pawn due to the fork on d6.}) (24... Qe7 $5) 25. c7 d3 {Black desperately tries to create some counterplay.} 26. Qc6 Qd4 27. Rc4 d2 28. Rd1 { Unlike White, Black cannot make any progress against the pieces opposing the passed pawn.} Qd3 29. Rxd2 Qb1+ 30. Rc1 {White's well-coordinated pieces now dominate the board and the rout is on.} Qxb4 31. Rd7+ Kh6 32. Nxf6 Rxf6 33. Qxf6 Qg4 34. Qg7+ 1-0

08 May 2013

Commentary - 2013 U.S. Championships, Round 4

Round 4 of the championships featured both Gata Kamsky and Irina Krush winning again to keep their perfect (4-0) start.  For me the most relevant game was Krush-Belakovskaia, with both players coming off victories in the earlier round.  Black employs a somewhat strange hybrid of English variations, an experiment which backfires as Krush appears comfortable in the novel position, while Black's pieces become progressively more uncoordinated and her counterplay on the kingside is neutralized by White.  Krush then plays the endgame masterfully, having inflicted multiple weaknesses on Black during the middlegame, and brilliantly calculates ahead to the winning K+P endgame position.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.06"] [Round "4.2"] [White "Krush, Irina"] [Black "Belakovskaia, Anjelina"] [Result "1-0"] [ECO "A35"] [WhiteElo "2470"] [BlackElo "2263"] [Annotator "ChessAdmin/Houdini"] [PlyCount "123"] [EventDate "2013.??.??"] [TimeControl "6000+1075"] [WhiteClock "0:11:17"] [BlackClock "0:02:42"] 1. c4 e5 2. Nc3 c5 3. Nf3 Nc6 {while the move order is unusual, the line of the Symmetrical English with ...e5 is popular at high levels.} 4. g3 f5 { this pawn thrust, however, is not. The usual step here is for Black to fianchetto his dark-square bishop, as shown by this top-level clash between Kramnik and Carlsen.} (4... g6 5. Bg2 Bg7 6. O-O Nge7 7. a3 a5 8. Ne1 d6 9. Nc2 O-O 10. d3 Rb8 11. Rb1 Be6 12. b4 axb4 13. axb4 cxb4 14. Nxb4 Nxb4 15. Rxb4 d5 16. cxd5 Nxd5 17. Nxd5 Bxd5 18. Rb5 Bxg2 19. Kxg2 Qd7 20. Qb3 Rfc8 21. Bb2 Qd6 22. Rb1 Rc5 23. Rb6 Rc6 24. Rxb7 Rxb7 25. Qxb7 Rb6 26. Qc8+ Qf8 27. Qd7 h5 28. e4 Qd6 29. Qe8+ Qf8 30. Qd7 Qd6 31. Qxd6 Rxd6 32. Rd1 f5 33. f3 fxe4 34. fxe4 Rb6 35. Bc3 Rb3 36. Ba1 Kf7 37. Kf3 Ke6 38. h3 Bh6 39. Ke2 Bg5 40. Rg1 Bh6 41. h4 Kd6 42. Rd1 Ke6 43. Rf1 Rb4 44. Rd1 Rb3 45. Rg1 Kf6 46. Rh1 Ke6 47. Rd1 Kf6 48. d4 Re3+ 49. Kf2 Rxe4 50. dxe5+ Kf5 51. Rd7 Kg4 52. Rd6 Be3+ 53. Ke2 Bf4+ 54. Kd3 Re3+ 55. Kc4 Bxe5 56. Rxg6+ Kf3 57. Bxe5 Rxe5 58. Rg5 Re4+ 59. Kd5 Rg4 60. Ke5 Kxg3 61. Rxh5 Rxh4 62. Rxh4 Kxh4 {1/2-1/2 (62) Kramnik,V (2795) -Carlsen,M (2848) London 2012}) 5. d3 {White needs to prevent ...e4.} Be7 { usual is ... Nf6 here, retaining some flexibility for the bishop.} 6. Bg2 Nf6 7. O-O O-O {at this point White has a classic English formation, used most often against a KID setup or a closed formation with the ...f5 advance. Black has changed things up by playing ...c5, with more of a lock on b4 and d4, but also leaving behind a big hole on d5, which is the key square in the English for White.} 8. a3 Rb8 9. Rb1 {pursuing the standard queenside expansion idea of pushing the b-pawn. Note that the lack of a fianchettoed bishop on g7 means that White does not have to worry about protecting the Nc3, among other things. The text move is a novelty according to the database, but there are only two other games with this position, so perhaps it's not so much of a surprise.} Qe8 $14 {Houdini awards White a slight edge. White's pieces are certainly better coordinated and she enjoys a slight lead in development, along with good prospects on the queenside.} 10. Nd5 {a somewhat paradoxical aspect of the English in general is the willingness of White to play what appears to be a premature knight sally to d5, inviting an exchange and doubling his d-pawns. In practical terms, however, the d5 pawn can seriously cramp Black while the newly half-open c-file offers White good opportunities for pressuring Black while employing a minority attack using the a- and b-pawns.} Bd6 (10... Nxd5 { is also a bad idea in this specific position for tactical reasons, because the Nc6 gets chased off and there is no Bg7 to protect the e5 pawn.} 11. cxd5 Nd4 12. Nxe5) 11. e4 {Krush chooses to play in the center rather than on the queenside.} (11. b4 Nxd5 12. cxd5 Nd4 13. Re1 {would be the more standard way to play. A possible continuation would be} f4 14. Nd2 fxg3 15. hxg3 cxb4 16. Ne4 $14) 11... b5 12. Nxf6+ Rxf6 13. exf5 Rxf5 {the last sequence did away with Black's f-pawn, which often plays a key role in Black's kingside attack in these types of positions. The half-open f-file may look dangerous, but Blacks threats there are more easily neutralized by White. Also note the continuing lack of coordination among Black's pieces.} 14. Ng5 (14. cxb5 { is Houdini's preference, exchanging prior to making the knight thrust. The engine assesses that letting Black exchange first and then plant a knight on d4 leads to equality.} Rxb5 {the presence of the hanging rook on b5 subsequently allows the threat of Qg4-c4+ forking rook and king.} 15. Ng5 { and now} Be7 {doesn't work for tactical reasons:} 16. Qg4 Nd4 17. Bd5+ Kh8 18. Qxf5 Nxf5 19. Nf7+ Qxf7 (19... Kg8 20. Nd6+ Kf8 21. Nxe8 Kxe8 22. Re1 Nd4 23. Rxe5) 20. Bxf7 $16) 14... Be7 15. Ne4 $11 {White's immediate threats have evaporated and it's back to positional maneuvering.} (15. Qg4 {is a tactical way to play and is still good for White, but not nearly as threatening as in the above variation.} Rf8 {here Black can simply retreat the rook, for example. } 16. Bd5+ Kh8 17. Nxh7 d6 18. Qe4 Bf5 19. Qg2 Bxh7 20. Bxc6) 15... Ba6 16. Nc3 (16. cxb5 Bxb5 17. Nc3) 16... Kh8 (16... bxc4 {would seem to preempt White's threats on the queenside.}) 17. cxb5 Bxb5 18. Nxb5 Rxb5 $14 19. Bxc6 {White chooses to give up the strong Bg2 and the bishop pair for longer-term compensation in the form of the doubled c-pawns.} (19. Be3 $5) 19... dxc6 20. Bd2 Qd7 21. Bc3 {as is common in some of these variations, White's dark-square bishop takes a long time to be developed. Here Krush finds an excellent place for it.} Rb8 22. Qe2 Qd5 23. f3 (23. Qe4 {White is clearly not afraid of an endgame, given Black's weaknesses, and this would immediately and powerfully centralize her queen, forcing Black to lose a tempo because of the attack on the hanging Rf5.}) 23... Bd6 24. Kg2 Kg8 25. Qe4 Rbf8 26. Rbe1 {White simply ratchets up the pressure in the center, at no cost to herself. Black meanwhile is barely defending and cannot generate counterplay.} h5 27. h4 Qxe4 $16 { Black decides to reduce the pressure and heads into a major and minor piece ending, where White however has all the chances.} 28. dxe4 R5f7 29. Rd1 Bc7 30. Rd3 {deliberately provoking the lead c-pawn's advance, further weakening Black's formation.} c4 31. Rd2 a5 {using a prophylactic move to prevent Bb4, after which White further dominates the position.} 32. a4 Kh7 33. Rc2 Rb8 34. Rff2 Bb6 35. Rfe2 Rbf8 $2 {Houdini pegs this as the losing move. Black likely foresaw a positional crush and decided to deliberately imbalance the position in the hopes of generating some practical counterplay chances.} (35... Re8) 36. Bxe5 Rxf3 37. Bf4 $16 {White now has a comfortable plus, with material gain coming soon.} (37. Bd6 {is the more aggressive line preferred by Houdini, leveraging the passed pawn to good effect.} R8f7 38. e5 Rd3 39. Rxc4 (39. e6 { is also possible}) 39... Rd7 40. Rxc6 $18) 37... Rb3 38. Rxc4 {the weakened pawn is now snapped off.} Rf6 39. Be5 Rg6 40. Bc3 Bc7 {Black has too many weaknesses and cannot stop the e-pawn while protecting the rest of her position.} 41. Re3 Be5 42. Rc5 Bxc3 43. bxc3 Rb2+ 44. Kh3 Kh6 45. e5 Re6 46. Rxa5 Ra2 47. Ra8 Kg6 48. a5 c5 49. a6 Raxa6 50. Rxa6 Rxa6 51. e6 Ra8 52. g4 { an excellent move, the purposes of which is to activate her king.} hxg4+ 53. Kxg4 Re8 54. c4 Kf6 {this looks good for Black, but Krush has correctly calculated the resulting pawn ending as a win for White.} 55. e7 Rxe7 56. Rxe7 Kxe7 57. Kf5 Kf7 58. h5 Kg8 59. Ke5 Kh7 60. Kd5 Kh6 61. Kxc5 Kxh5 62. Kd5 { and after both pawns promote, White is ahead a tempo and can play Qh8+ followed by Qg8+ to skewer the king against the unprotected Qg1. If Black does not go for the pawn race, then White queens anyway.} 1-0

06 May 2013

Commentary - 2013 U.S. Championships, Round 3

The round 3 commentary on the official championships site has my two favorite games from the round, Kamsky-Christiansen and Zatonskih-Krush.  In the first one, Kamsky plays in Carlsen-esque style, using a quiet opening to get to a fascinating and ultimately explosive middlegame.  In the second, Krush plays an outstanding King's Indian and attacks on the kingside in exemplary style.  They are well worth a look.

Here I present another Caro-Kann, this time from the women's championship (Belaskovaia-Chiang).  While the previous day's example, Kachyan-Onischuk, was an illustration of how well the Classical variation can shut down White's play, the round 3 game shows some of the interesting, major choices both sides can face that will change the course of the game.  What happens to Black after she takes a "free" pawn is particularly instructive, as is White's conduct of the assault on Black's king position (on the queenside).  The clash between generations of U.S. women players is also interesting in itself, with IM Anjelina Belakovskaia as a three-time U.S. champion in the 1990s returning after a long layoff and Sarah Chiang as an up-and-coming junior gaining some valuable experience at the national level.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.05"] [Round "3.16"] [White "Belakovskaia, Anjelina"] [Black "Chiang, Sarah"] [Result "1-0"] [ECO "B19"] [WhiteElo "2263"] [BlackElo "2098"] [Annotator "ChessAdmin/Houdini"] [PlyCount "137"] [EventDate "2013.??.??"] [TimeControl "6000+800"] [WhiteClock "0:02:56"] [BlackClock "0:02:53"] 1. e4 c6 2. d4 d5 3. Nc3 dxe4 4. Nxe4 Bf5 5. Ng3 Bg6 6. Nf3 Nd7 7. h4 h6 8. h5 Bh7 9. Bd3 Bxd3 10. Qxd3 e6 11. Bf4 {the first deviation from the game we saw in round 2 (Metchik-Onischuk), which featured the other main choice, Bd2, in which White goes for more straightforward development. The text move is a little more aggressive but can sometimes transpose back, if both players allow; however, that doesn't occur in this game.} Qa5+ {the standard response.} 12. Bd2 Bb4 {Black scores quite well in this line (54 percent).} (12... Qc7 { is the old Caro-Kann main line, where both sides usually castle queenside. It has a solid but un-dynamic reputation.}) 13. c3 Be7 14. c4 Qc7 {this move is the overwhelming favorite, but Black ends up in a position-type similar to the old main line, with queenside castling.} (14... Qa6 {is an interesting idea played by some professional Caro-Kann players such as Bareev and Khenkin who aren't afraid to try new things. Here's a game by Khenkin:} 15. O-O Ngf6 16. Rfe1 Rd8 17. Qe2 O-O 18. Ne5 c5 19. Bc3 cxd4 20. Bxd4 Nxe5 21. Bxe5 Qa5 22. Qf3 Rd7 23. Bc3 Qa6 24. Ne4 Nxe4 25. Qxe4 Rc8 26. Rad1 Rxd1 27. Rxd1 Qxc4 28. Qxb7 Bf6 29. Bxf6 gxf6 30. Qxa7 Rc5 31. a4 Rxh5 32. Qd4 Qe2 33. Ra1 Kg7 34. b4 Rd5 35. Qc3 Rd1+ 36. Rxd1 Qxd1+ 37. Kh2 Qxa4 38. Qc5 h5 39. b5 Qf4+ 40. Kg1 Qe4 41. b6 e5 42. Qb5 Qe1+ 43. Kh2 Qxf2 44. Qb4 e4 45. b7 Qf4+ 46. Kg1 Qe3+ 47. Kf1 Qd3+ 48. Ke1 Qe3+ 49. Kf1 Qd3+ 50. Ke1 Qe3+ 51. Kf1 Qf4+ {1/2-1/2 (51) Smeets, J (2515) -Khenkin,I (2587) Hoogeveen 2004}) 15. O-O-O Ngf6 16. Rde1 O-O-O { interestingly, all of Black's options score 50 percent here, although with a relatively small database sample. I would personally prefer to castle kingside here, although White looks to have good attacking possibilities afterwards, since Black would have much a freer hand on the queenside and center.} 17. Qe2 Rhe8 $146 (17... Ng4 {was played in the only game in the database with this position. This seems like an effective move for the knight as it helps cover e5 and eyes f2.} 18. Kb1 Rhe8 19. Bc3 Kb8 20. Nd2 Ngf6 21. Nge4 Nxe4 22. Nxe4 f5 23. Nd2 Bf6 24. Nb3 e5 25. Qf3 exd4 26. Nxd4 Ne5 27. Qxf5 Nxc4 28. Ne6 Rxe6 29. Qxe6 Bxc3 30. Qxc4 Bxe1 31. Rxe1 Qa5 32. Qf4+ Ka8 33. Qe5 Qd2 34. Qe3 Qd7 35. Qe4 Qf7 36. Qe7 Qf5+ 37. Ka1 Qd5 {1/2-1/2 (37) Al Modiahki,M (2550)-Landa, K (2570) Bad Wiessee 2006}) 18. Kb1 {the king needs to get off the c-file and away from the c1-h6 diagonal, which are latent potential tactical weaknesses. The move also covers a2.} Bd6 19. Rh4 c5 {Black as available to her both of the classic Caro-Kann pawn breaks, on c5 and e5. With the king on c8, I would prefer the e5 break.} (19... e5 20. c5 Bf8 21. Nxe5 Bxc5) 20. Ne4 Nxe4 21. Qxe4 {capturing with the rook seems like a more obvious follow-up to her 19th move.} Nf6 (21... cxd4 {is preferred by Houdini, pressing on with the opportunity provided by the pawn break to disrupt White's center and leaving c5 for the knight.} 22. Nxd4 Be7 23. Nb5 Qb6 24. Rh3 a6) 22. Qc2 cxd4 23. Nxd4 Bc5 { compare Black's piece placement with the move 21 variation, which seems more effective.} 24. Nb5 Qc6 25. Be3 (25. b4 {would be the aggressive choice and would take advantage of the Rh4 placement to support the fourth rank.} a6 26. bxc5 axb5 27. cxb5 Qxb5+ 28. Rb4) 25... Bxe3 26. fxe3 {this doesn't seem to have been a very effective trade for White, who is now saddled with the isolated e-pawn, although her pieces are more active. Note how the Nf6 is poorly placed, with most of its squares taken away, so it should reposition itself, probably via d7.} Qc5 (26... Kb8 {is Houdini's choice, with the king vacating the c-file, covering a7 and enjoying the fact there is no longer a White dark-square bishop.}) 27. a3 a6 28. Nc3 Qg5 $15 {Black is starting to generate some threats and take over the initiative here.} 29. Rh3 Nxh5 { Black however gets distracted by the pawn and White quickly regains the initiative. The knight is effectively out of the game on h5, which White immediately takes advantage of.} (29... Kb8 $5) 30. Ne4 Qe5 31. c5 Re7 32. Nd6+ Kb8 33. b4 Nf6 {Black understands the need to get the knight back in the fight. } 34. e4 Rc7 35. Rd3 Rdd7 $2 {leaving the queen on a vulnerable square.} (35... Qf4 {looks reasonable, keeping pressure on e4.}) 36. Nc4 Qg5 37. Nb6 {suddenly Black has no way to avoid White's threats from the heavy pieces on the d-file and the Nb6, which threaten mate or significant material loss.} Ka7 (37... Rxd3 38. Qxd3 Ng8 (38... Ng4 39. Rd1 Ka7 40. Qd8 Qxd8 41. Rxd8 {and Black gets mated in the corner.}) 39. Rf1 {and now White can follows up with Qd6 and Rd1.} ) (37... e5 38. Red1 Qg4 39. Nxd7+ Nxd7 $18 {with a crushing position.}) 38. Nxd7 $16 {White takes the safe advantage.} (38. Red1 $18 {would lead to a much larger advantage, due to White's theats down the d-file leading to mate threats.}) 38... Nxd7 39. Qd2 Qe7 40. Qf4 e5 41. Qg4 f6 42. Red1 Qf7 43. Kb2 { this covers the b3 square.} (43. Rxd7 $2 Qb3+ {with a perpetual.}) 43... Nf8 $2 {this withdraws a defender from Black's king and again White pounces on the errant knight move.} (43... Nb8) 44. Rd6 $18 g6 45. Rf1 h5 46. Qh3 Nh7 47. Qe3 {Black's knight is now almost buried again on h7 and White has too much firepower for Black to repel.} Rc6 48. Rxc6 bxc6 49. Qd2 Kb7 50. Qd8 Qc7 51. Qe8 {an excellent example of when not to trade down when you are in a much stronger position.} Qc8 52. Qxg6 Qd7 53. Kc2 {White continues to effectively employ her king to shut out Black's queen from penetrating, as well as preparing to move the rook to the d-file.} h4 54. Rd1 Qe7 55. Rd6 {White now completely dominates.} Kc7 56. Kd3 Kb7 57. Qg4 Nf8 58. Qf5 Qf7 59. Qxf6 Qb3+ 60. Ke2 Qc4+ 61. Kf2 Qc2+ 62. Kg1 Qc1+ 63. Kh2 Qf4+ 64. Qxf4 exf4 65. Rf6 { the correct moment for the queens to come off the board occurred and the win is now trivial.} Nd7 66. Rf7 Kc8 67. Rxf4 Ne5 68. Rxh4 Nc4 69. Rh3 1-0

05 May 2013

Commentary - 2013 U.S. Championships, Round 2

For Round 2 of the U.S. Chess Championships I found an embarrassment of riches - 5 games that I thought were particularly relevant to my chess training and studies, not just one.  I was fortunate to be able to see a large portion of the excellent live coverage for round 2 as well, giving me some ideas of which games were the most interesting to me personally, along with some specific observations and ideas from the commentary.

Game 1: IM Kayden Troff - GM Gata Kamsky
Kamsky brings out the Leningrad Dutch, which his opponent likely was not fully prepared for, judging by the novelty on move 7.  Black makes a strategic exchange sacrifice and then takes over the initiative and outplays his opponent.  I found both the opening discussion and the idea and execution of the positional exchange sacrifice very useful to see.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.04"] [Round "2.1"] [White "Troff, Kayden"] [Black "Kamsky, Gata"] [Result "0-1"] [ECO "A86"] [WhiteElo "2421"] [BlackElo "2741"] [Annotator "ChessAdmin/Houdini"] [PlyCount "64"] [EventDate "2013.??.??"] [TimeControl "6000+1455"] [WhiteClock "0:01:28"] [BlackClock "0:10:01"] 1. d4 f5 2. c4 Nf6 3. Nc3 d6 {Leningrad Dutch players use this move-order to avoid giving a target to a quick h4-h5 attack by White.} 4. g3 (4. h4 {is now rarely played, but has been highly effective, scoring 80 percent in the database, including against strong Black players. Black can now play in the center, however, and is not committed to g6. An example:} e5 5. dxe5 dxe5 6. Qxd8+ Kxd8 7. Nf3 Nbd7 8. e4 f4 9. g3 fxg3 10. fxg3 Bb4 11. Bg5 h6 12. Bxf6+ gxf6 13. Rc1 Rg8 14. Kf2 c6 15. Bd3 Ke7 16. a3 Bc5+ 17. Kg2 a5 18. h5 Be3 19. Rce1 Bf4 20. Ne2 Nc5 21. Bc2 Be6 22. Kf2 Bg5 23. b3 Bg4 24. Rd1 Rad8 25. Nc3 Rxd1 26. Bxd1 Rd8 27. Nh4 Rd2+ 28. Kf1 Bxd1 29. Nf5+ Ke6 30. Ke1 Nd3+ {0-1 (30) Hambleton,A (2052)-Barron,M (2241) Edmonton 2009}) 4... g6 5. Bg2 (5. h4 { has never been played in this position in the database, but the following game is an example by transposition at the professional level.} c6 6. Bg2 Qa5 7. Bd2 Qa6 8. b3 Bg7 9. d5 O-O 10. Nh3 cxd5 11. cxd5 Nbd7 12. Nf4 Ne5 13. h5 Bd7 14. hxg6 hxg6 15. Be3 Nfg4 16. Bd2 Qb6 17. O-O Rfc8 18. Rc1 Bf6 19. e3 {1/2-1/2 (19) Djurhuus,R (2495)-Sahl,B (2455) Gausdal 1995}) 5... Bg7 6. Nh3 { characteristic of the Karlsbad variation. White chooses not to block the Bg2 and normally looks to move the knight to f4.} e6 {an uncommon move here, although e6 is played in the main line Karlsbad. The pawn move has the dual purpose of contesting d5 and allowing Black the option of playing an eventual . ..e5 if White pushes d5.} (6... c6 {scores 50 percent in the database and is the popular choice for those not wanting to commit the knight via ...Nc6.}) 7. Qa4+ $146 {this early queen sortie has not been played before in the database. Castling or playing Nf4 are the two most popular options.} c6 8. d5 O-O 9. dxe6 Bxe6 $11 {this is another idea behind the earlier e6, to allow the pawn exchange and bishop development.} 10. Ng5 Bc8 {an interesting choice, disallowing the knight for bishop exchange. Black's bishop currently is quite confined, but may have good long-term prospects.} 11. O-O Qe7 12. Qa3 Nbd7 13. Rd1 Ne8 {this sort of passive defense seems like an attempt to bait White into overextending himself.} (13... h6 14. Nh3 Ne5 {and now} 15. Qxd6 Qxd6 16. Rxd6 Nxc4 {seems good for Black.}) 14. Be3 Ne5 {Kamsky must have seen the following sequence (except perhaps for the move 16 variation) and evaluated that he could play the position following the exchange sac better than his opponent.} 15. c5 dxc5 16. Bxc5 (16. Nd5 {is what Houdini comes up with, a far from obvious move that however gives White an attack.} cxd5 17. Bxd5+ Kh8 18. Bxc5 Qxg5 19. Bxf8 $16 {with strong pressure and open lines in the center for White to exploit, for example} Qf6 20. Bxg7+ Kxg7 21. Rac1) 16... Qxg5 17. f4 Qf6 18. fxe5 Qxe5 19. Bxf8 (19. Rd8 {here would be annoying for Black, an idea flagged by the live commentators.}) 19... Bxf8 20. Qb3+ Kg7 $11 {Houdini evaluates this as equal, despite the small material imbalance in White's favor. Kamsky must have been confident that he could exploit his longer-term structural advantages and White's weaknesses (such as the e-pawn), despite his own backward development. The collection of pieces on the 8th rank is impressive in that regard.} 21. Bf3 {White's first move that goes a bit astray.} (21. Rd8 {now doesn't work due to} Nd6 {effectively trapping the rook, forcing White to give back the exchange.}) (21. e4 {was Seirawan's idea during the live commentary and is also Houdini's favorite. White looks to exchange off the weak pawn, or if Black leaves it on the board, gain some control over the center.}) 21... Nd6 22. Na4 Nb5 23. Qd3 Be6 $15 {compare this position with three moves earlier, Black looks much better positioned while White has essentially done nothing constructive.} 24. Kg2 g5 {signals that Black has taken over the initiative.} 25. Kh1 Be7 26. Qc2 g4 27. Bg2 h5 {Black now has a kingside attack rolling with all of his pieces poised to participate (even the knight can jump in via d4). In constrast, White's pieces are spread out and uncoordinated.} 28. e4 h4 29. exf5 Bxf5 30. Qc4 h3 {with the pawn on h3 and open lines available for Black's pieces to attack White's king, the end is near.} 31. Re1 hxg2+ 32. Kxg2 Qf6 $19 {Houdini evaluates the position as the equivalent of Black being up a piece.} 0-1

Game 2: GM Gregory Kaidanov - GM Conrad Holt
It's always difficult to face your own favorite defense as White, so this game was personally important, as I've struggled to come up with a good reply after 1...c6.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.04"] [Round "2.5"] [White "Kaidanov, Gregory"] [Black "Holt, Conrad"] [Result "1/2-1/2"] [ECO "A11"] [WhiteElo "2593"] [BlackElo "2513"] [Annotator "ChessAdmin/Houdini"] [PlyCount "120"] [EventDate "2013.??.??"] [TimeControl "6000+1205"] [WhiteClock "0:05:11"] [BlackClock "0:00:40"] 1. c4 c6 2. Nf3 {an independent English variation. Naturally White could transpose to a queen or king's pawn opening here.} d5 3. g3 Nf6 4. Bg2 dxc4 5. O-O Nbd7 6. Na3 (6. Qc2 {is the other main option.} Nb6 7. a4 (7. Na3 { transposing})) 6... Nb6 7. Qc2 Be6 {this position demonstrates White's objective with sacrificing the pawn. Black's kingside is underdeveloped and his king is in the center, while White has a lead in development and is pressuring hard to regain his pawn.} 8. Ne5 (8. Ng5 {is played the most, but only scores 45 percent for White. The text move scores 52 percent.}) 8... Qd4 9. Nxc6 bxc6 10. Bxc6+ Kd8 11. Bxa8 {only a handful of games in the database now, the only game with this move being a White loss.} (11. Nb5 {is Houdini's choice and was most recently played by Timman in Wijk aan Zee:} Qc5 12. Bxa8 Qxb5 13. Bg2 h5 14. h4 Bf5 15. e4 Bd7 16. a4 Nxa4 17. e5 Ne8 18. Re1 e6 19. Bf1 Bc5 20. d3 Qb3 21. Qxc4 Qxc4 22. dxc4 Nc7 23. Rd1 Kc8 24. Rxd7 Kxd7 25. Rxa4 Rb8 26. Be2 g6 27. Bd1 Bd4 28. b3 a6 29. Bf4 Bc3 30. Ra2 Kc6 31. Kf1 a5 32. Bd2 Bb4 33. Bxb4 axb4 34. Bf3+ Kb6 35. c5+ Kb5 36. Rd2 Nd5 37. Bxd5 exd5 38. Rxd5 Rb7 39. Ke2 Kc6 40. Rd3 Re7 41. f4 Ra7 42. f5 gxf5 43. Kf3 Ra1 44. Kf4 Rf1+ 45. Kg5 Kxc5 46. Kxh5 Rc1 47. Rf3 Rc3 48. Rxf5 Kd5 49. g4 Ke6 50. Rf6+ Ke7 51. g5 Rxb3 52. e6 fxe6 53. Kg6 Rh3 54. h5 b3 55. h6 {1-0 (55) Timman,J (2566)-Smeets, J (2615) Wijk aan Zee NED 2013}) 11... Nxa8 {in contrast with the other line, now White no longer has the two bishops.} 12. d3 cxd3 13. Rd1 dxc2 14. Rxd4+ Bd7 15. Nxc2 e5 16. Rd1 Nb6 17. Be3 Kc7 18. Ne1 {during the live commentary, a small preference was given to Black here because two pieces usually are more powerful than a rook. Black also has plenty of good squares for his pieces at this point.} Nfd5 19. Rac1+ Kb7 20. Bc5 {standard practice when your opponent has the two bishops is to trade one of them off.} Bxc5 21. Rxc5 Be6 22. Nd3 e4 23. Ne5 {Houdini evalutes this position as completely equal. Despite the R+P vs. B+N imbalance in his disfavor, White's rooks are well-placed as is his knight, while Black's king looks a little precarious.} Ne7 24. Rd4 f6 {this may have been a psychological turning point in the game, as White afterwards starts to gain some initiative. The eventual tactical point of White's sequence may not have been seen.} (24... Bd5 $5) 25. Rxe4 Bd5 26. Rg4 fxe5 27. Rxg7 {pinning the Ne7, which either results in the return of a piece (leaving White two pawns to the good) or ties Black up in knots.} Re8 28. e4 Bg8 29. Rxe5 Nbc8 30. b3 $14 {the material balance in a rough sense somewhat favors Black, but the dominance of the White rooks and Black's passive piece placement, along with White's mobilizing passed pawns, give White an advantage. } Kc7 31. f4 Kd6 32. Kf2 Rf8 33. Ke3 Nc6 34. Rh5 N8e7 35. h4 Ke6 36. g4 Kf6 37. Rgg5 {the live commentary picked things up again here, noting how the rook and pawn activity and related space advantage was in White's favor. The position is tough to play, however, and neither player is likely to have much in the way of similar experience to draw on.} Rd8 38. Rc5 (38. Rh6+ Kf7 39. Rc5 $16 { is Houdini's preference, pushing the king back before playing ...Rc5.}) 38... Kg7 39. Rc3 Rd1 40. Rg5+ Kf8 $11 {here Houdini gives a slight edge to Black, who has managed to activate his pieces and get his king to a less vulnerable square.} 41. f5 Rd6 (41... Ne5 $5) 42. Rc5 h6 (42... Bf7) 43. e5 {Houdini thinks this is winning for Black.} (43. Rxg8+ Kxg8 44. a3 $15) 43... Rd5 44. Rxg8+ Kxg8 45. Rxd5 Nxd5+ 46. Kf3 Nc3 47. e6 Nxa2 48. g5 hxg5 49. hxg5 Nc3 50. Ke3 Kf8 51. Kd3 Nd5 52. Kc4 Nc7 (52... Ne3+) 53. Kc5 Nb8 {now White's king pushes forward and Houdini evaluates the position as equal. White threatens to push the pawns forward with the king's help, but cannot escape from the Black knights' harrassment.} 54. Kd6 Ne8+ 55. Kd5 Nc7+ 56. Kd6 Nb5+ 57. Kc5 Nc3 58. Kd6 Nb5+ 59. Kc5 Nc3 60. Kd6 Nb5+ 1/2-1/2

Game 3: GM Melik Kachyan - GM Alex Onischuk
This is an excellent example of a solid Caro-Kann Classical, whose main line goes out quite far (around move 20).  Black neutralizes White's threats and plays solidly, although White perhaps could have tried for a little more towards the end.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.04"] [Round "2.6"] [White "Khachiyan, Melik"] [Black "Onischuk, Alex"] [Result "1/2-1/2"] [ECO "B19"] [WhiteElo "2518"] [BlackElo "2666"] [Annotator "ChessAdmin/Houdini"] [PlyCount "71"] [EventDate "2013.??.??"] [TimeControl "6000+1225"] [WhiteClock "0:24:42"] [BlackClock "0:11:10"] 1. e4 c6 2. d4 d5 3. Nc3 dxe4 4. Nxe4 Bf5 5. Ng3 Bg6 6. h4 h6 7. Nf3 Nd7 8. h5 Bh7 9. Bd3 Bxd3 10. Qxd3 e6 11. Bd2 Ngf6 12. O-O-O Be7 13. Ne4 Nxe4 14. Qxe4 Nf6 15. Qe2 Qd5 16. c4 Qe4 17. Qxe4 Nxe4 18. Be3 {a standard opening line to this point, where we now have a queenless middlegame that can simplify quickly into an endgame.} Nd6 {a solid choice that scores 50 percent for Black.} (18... f5 {scores the best here, with 56 percent for Black.}) (18... O-O {is the most popular, but only scores 47 percent for Black.}) 19. Ne5 Bf6 20. b3 Nf5 21. Nf3 b5 22. g4 {first move out of the database.} Nxe3 23. fxe3 bxc4 24. bxc4 c5 { a typical pseudo-sacrifice that if accepted would give Black a small advantage. } 25. Kc2 (25. dxc5 Rc8 26. Rd2 Rxc5 27. Rc2 Ke7 $15 {and Black has two isolated pawns to target.}) 25... O-O 26. Kd3 Rac8 27. Rh2 Rfd8 28. Rc2 Rd6 29. Ke4 Rb6 30. Rd3 Rb4 (30... Ra6 {would be safer.}) 31. Rb3 (31. Ra3 $5 cxd4 32. exd4 Rbxc4 33. Rxc4 Rxc4 34. Rxa7) 31... Ra4 32. Rb7 Rc6 33. Rb8+ Kh7 34. Rb7 Kg8 35. Rb8+ Kh7 36. Rb7 1/2-1/2

Game 4: GM Alejandro Ramirez - GM Alexander Ivanov
The opening phase is very interesting, morphing from a Hedgehog to a Symmetrical English to a Benoni structure.  White has a comfortable game afterwards, although not a winning advantage.  The explosion of tactics starting on move 19 comes from what appears to be just a small Black inaccuracy.  White aggressively pushes the passed pawn he wins as a result and leverages other associated tactical opportunities to ram home the point.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.04"] [Round "2.9"] [White "Ramirez, Alejandro"] [Black "Ivanov, Alexander"] [Result "1-0"] [ECO "A30"] [WhiteElo "2551"] [BlackElo "2544"] [Annotator "ChessAdmin/Houdini"] [PlyCount "67"] [EventDate "2013.??.??"] [TimeControl "6000+1640"] [WhiteClock "0:35:30"] [BlackClock "0:02:06"] 1. Nf3 Nf6 2. c4 b6 3. g3 c5 4. Bg2 Bb7 5. O-O Nc6 {this move varies from a the typical Hedgehog setup.} 6. Nc3 g6 7. e3 (7. d4 {would be the standard analagous continuation in a Hedgehog and in fact scores over 70 percent for White. The text move also scores well, 65 percent.}) 7... Bg7 8. d4 {now White would be able to replace the pawn on d4 if it is exchanged.} O-O 9. d5 { as Black declines to exchange on d4, White now grabs space with d5. The pawn structure is now that of a more typical queen's pawn opening.} Na5 10. Qd3 e6 { Black decides to immediately challenge the head of the pawn chain.} 11. e4 exd5 12. exd5 d6 {now we have a Benoni-type structure. White appears to have a comfortable game.} 13. Bf4 Bc8 14. b3 Bf5 15. Qd2 Re8 16. Rae1 Qd7 $6 {this cuts off the retreat squares for the Bf5.} (16... Nb7 $5) 17. Nh4 Nb7 18. Nb5 { this perhaps was played to see if Black would go wrong before the capture.} ( 18. Nxf5) 18... Nh5 {and Black does. The d6 pawn is vulnerable after the exchange on f5.} (18... Be4) 19. Nxf5 Qxf5 (19... gxf5 20. Rxe8+ Rxe8 21. Nxa7 Nxf4 22. Qxf4 Re2 23. Nb5 h6 24. Bh3 Qe8 (24... Rxa2 25. Re1) 25. a3 $18) 20. Bxd6 Rxe1 21. Rxe1 Nxd6 22. Nxd6 $16 {White is now up a protected passed pawn and Black has no compensation for it.} Qd7 23. Nb5 a6 24. d6 {aggressively pushing the pawn whenever possible. Here the discovered attack on the Ra8 is the tactical mechanism.} Rd8 (24... Re8 $5 $16) 25. Re7 $18 Qf5 26. Nc7 (26. Bd5 {is Houdini's recommended tactic.} axb5 27. Rxf7 Qxf7 28. Bxf7+ Kxf7 29. Qd5+ Kf8 30. Qc6 $18) 26... Nf6 27. Bd5 Nxd5 28. Nxd5 Bf8 29. d7 {more tactics allow the passed pawn push.} Qb1+ (29... Rxd7 $2 30. Rxd7 Qxd7 31. Nf6+) 30. Re1 Qf5 31. Re8 {White now finishes off his opponent with a tactical flourish.} Rxd7 32. Qh6 Qb1+ 33. Kg2 Qe4+ 34. Rxe4 {Black now loses the rook, not having the time to both recapture the queen and move out of the way of the fork with Nf6+} 1-0

Game 5: Sarah Chiang - IM Anna Zatonskih
Zatonskih transposes into a Modern Dutch Stonewall formation by move 6, after starting off with a Slav defense.  Her opponent appears unfamiliar with some key positional ideas, such as the importance of not opening the f-file and trying to maintain a knight on e5.  Despite this, White manages to stay equal after Black fails to follow up on a few opportunities.  In the resulting equal double bishop endgame, Black simply outplays her opponent in an instructive manner.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.04"] [Round "2.14"] [White "Chiang, Sarah"] [Black "Zatonskih, Anna"] [Result "0-1"] [ECO "A85"] [WhiteElo "2098"] [BlackElo "2466"] [Annotator "ChessAdmin/Houdini"] [PlyCount "86"] [EventDate "2013.??.??"] [TimeControl "6000+1700"] [WhiteClock "0:18:07"] [BlackClock "0:23:43"] 1. d4 d5 2. c4 c6 3. Nf3 e6 4. e3 f5 {naturally Black has several options here; Zatonskih goes for a Stonewall.} 5. Nc3 Nf6 6. Bd3 Bd6 {the Modern Stonewall formation is now complete.} 7. O-O O-O 8. Qc2 Ne4 9. Ne5 Nd7 {this is the most popular continuation and scores 50 percent for Black in the database. Black chooses to avoid exchanging off her dark-square bishop.} (9... Bxe5 10. dxe5 Nd7 {is an alternative line that scores better than 50 percent for Black.}) 10. f3 Nef6 {a rare move.} (10... Nxc3 {is by far the most played here, for example } 11. Qxc3 Nxe5 12. dxe5 Be7 13. Bd2 Qb6 14. Kh1 Bd7 15. Rad1 Kh8 16. Bc1 Be8 17. Bb1 Bh5 18. a3 a5 19. Rd4 g5 20. Re1 g4 21. fxg4 Bxg4 22. h3 Bh5 23. Rf1 Bg5 24. b4 axb4 25. axb4 c5 26. Rd2 cxb4 27. Qb3 Bxe3 28. Rc2 Bxc1 29. Rfxc1 Ra3 30. Qb2 d4 31. c5 Qc6 32. Qxd4 Rxh3+ 33. Kg1 Rg8 34. Rf2 Rhg3 35. Rcc2 Bf3 {0-1 (35) Nazarov,V (2152)-Nagimov,A (2344) Dagomys 2004}) 11. Nxd7 (11. f4 { would be more usual here, keeping the Ne5 established on its square.}) 11... Bxd7 12. e4 $6 {this greatly assists Black's typical plan of opening the f-file for attacking purposes.} (12. b3 {would be a standard way to develop the bishop}) (12. c5 $5) 12... fxe4 13. fxe4 e5 {posing a complex choice for White in the center.} (13... Ng4 {is Houdini's move, with an immediate threat to the h2 pawn.} 14. Rxf8+ Qxf8 15. g3 dxc4 16. Bxc4 {and now} Bc5 {is the key tactic, gaining Black the d-pawn, since} 17. dxc5 $2 Qxc5+ 18. Kg2 Qxc4 $19) 14. exd5 {the engine indicates this is the incorrect selection.} (14. c5 exd4 15. cxd6 dxc3 16. Be3 $11 Qe8 (16... cxb2 $6 17. Qxb2 {and now White threatens the pawn on b7 and pushing e5.})) 14... exd4 15. Ne4 Nxe4 16. Rxf8+ Qxf8 17. Bxe4 h6 {Black takes a moment to move the pawn out of the B+Q battery.} (17... Qf6 {as a more aggressive continuation was also possible, accelerating Black's threats to White's vulnerable king. For example} 18. Bxh7+ $2 Kh8 19. Bd3 Re8 20. Bd2 Qh4 21. g3 Bxg3 $19) 18. Bd2 Re8 {Houdini again likes ...Qf6 here.} 19. Re1 Kh8 {getting out of the way of future potential checks along the g8-a2 diagonal following an exchange on d5, as well as Bh7+.} 20. Qd3 Qf6 21. Qf3 ( 21. dxc6 {would ensure that Black' s queenside pawns are split in the coming endgame.}) 21... Qe5 22. g3 Rf8 23. Qg2 Qh5 24. Rf1 Rxf1+ 25. Qxf1 c5 {the engine evaluates the position as completely equal, not surprising given its symmetry.} 26. Bc2 Kg8 27. Qd3 Kf7 {Black decides to get her king closer to the center before offering an exchange of queens.} 28. Qe4 Qg4 29. Qxg4 Bxg4 { somewhat paradoxically, with the queens off it makes it more difficult for White in practical terms. Now Zatonskih gives a lesson in how to play bishop endings.} 30. Kf2 Kf6 31. Bd3 g5 32. Bf1 {this withdrawal allows Black to immediately seize a key diagonal.} Bf5 33. Be2 Be4 34. h3 b5 {a provocative move that appears to have rattled her opponent.} 35. b3 (35. cxb5 Bxd5 36. b3 { and now Black cannot penetrate on the queenside.}) 35... b4 36. Bd1 Bb1 { the move that seals White's fate.} 37. Bc1 Bxa2 38. Bc2 a5 39. Bb2 Be5 40. Bd1 a4 41. bxa4 Bxc4 42. Bf3 d3 43. Bc1 b3 0-1

04 May 2013

Commentary - 2013 U.S. Championships, Round 1

During the ongoing 2013 U.S. Championships, I'll provide commentary on one game each round, if I find one that is of particular personal interest.  Below is a game from Round 1 featuring longtime favorite GM Larry Christiansen as White against Yaacov Norowitz, who essays the always interesting (if unbalanced) Bronstein-Larsen variation of the Caro-Kann.  The opening requires Black to play energetically and try for a kingside attack whenever possible, but here it doesn't quite get going for him.  White is in control from around move 21 on, although Black puts up a dogged resistance.  The endgame is won after Christiansen returns his extra pawn in exchange for a dominant king.  Not a good result for fans of the Bronstein-Larsen, but well worth looking at regardless.

[Event "2013 U.S. and Womens' Championship"] [Site "Saint Louis, Missouri, USA"] [Date "2013.05.03"] [Round "1.11"] [White "Christiansen, Larry"] [Black "Norowitz, Yaacov"] [Result "1-0"] [ECO "B16"] [WhiteElo "2579"] [BlackElo "2451"] [Annotator "ChessAdmin/Houdini"] [PlyCount "97"] [EventDate "2013.??.??"] [TimeControl "6000+865"] [WhiteClock "0:31:19"] [BlackClock "0:26:31"] {B16: Caro-Kann: Bronstein-Larsen Variation} 1. e4 c6 2. d4 d5 3. Nc3 dxe4 4. Nxe4 Nf6 5. Nxf6+ gxf6 6. Nf3 {although this is the second most popular move and is played at high levels over-the-board, theory mostly ignores it in favor of 6. c3.} Bg4 {why the previous move is considered theoretically less desirable. Normally the bishop has to go to f5 instead.} 7. Be2 e6 8. O-O Qc7 { Bd6 is more popular here, although both prevent White from playing Bf4.} 9. Nh4 {White scores 75% from here.} Bxe2 10. Qxe2 Nd7 11. c4 O-O-O {obligatory, as the king has nowhere else to go.} 12. Rd1 {White has tried a lot of things in this position, but 12. g3 is by far the most played, with the idea of shutting down Black's play on the g-file. Here are two games where Black managed to draw.} (12. g3 h5 (12... Rg8 13. d5 Qe5 14. Be3 Qe4 15. dxc6 Ne5 16. cxb7+ Kxb7 17. Qh5 Qxc4 18. Rad1 Rxd1 19. Rxd1 Rg4 20. Ng2 Qc2 21. Rc1 Qg6 22. Qxg6 Rxg6 23. f4 Nc6 24. Rd1 Be7 25. f5 Rg8 26. Kf2 e5 27. Kf3 Kc7 28. Rc1 h5 29. b3 a5 { 1/2-1/2 (29) Asis Gargatagli,H (2431)-Alvarez Pedraza,A (2551) Barcelona 2011}) 13. d5 Re8 14. dxe6 fxe6 15. Bf4 Bd6 16. Bxd6 Qxd6 17. Rad1 Qc7 18. Rd2 Ne5 19. Rfd1 Kb8 20. b3 a6 21. Rd6 Qb6 22. Kg2 Qa5 23. Kh1 c5 24. Nf3 Nc6 25. Kg1 h4 26. Rxe6 Rxe6 27. Qxe6 {Talla,V (2335)-Jankovec,I (2240) Czechia 1998 1/2-1/2 (41)}) 12... c5 {this is a standard break in the Caro-Kann main line, the idea being to help activate Black's pieces. With Black castled queenside it requires a little more bravery.} 13. d5 {White would of course welcome an exchange on d5, leaving Black with no central pawns and a horrendous pawn structure on the kingside.} Ne5 (13... Bd6 {is suggested by Houdini. Black is falling behind in development and needs to generate kingside threats.} 14. dxe6 {is not a refutation because of} fxe6 15. Qxe6 Bxh2+ 16. Kf1 Be5) 14. Bf4 Bd6 15. dxe6 fxe6 16. Bxe5 fxe5 {at this point it's clear that Black's shattered and vulnerable pawn structure will be the central focus of the remainder of the game.} (16... Bxe5 {appears somewhat better, although still difficult for Black, as the Bishop can be a target as well on e5 and has few places to go.} 17. Nf3) 17. g3 Qf7 {with the g-file closed after the previous move, the f-file is the only possible avenue of attack. This seems to have been the rationale for taking with the pawn on e5, in order to have it influence f4.} 18. Rd2 Rhf8 19. Kg2 Rd7 (19... Bc7 {is Houdini's recommendation.} 20. Rxd8+ Rxd8 21. Re1 $16) 20. Rad1 Rfd8 21. Qe4 {White's pieces are more mobile and threatening than Black's. At this point Black focuses on defense, in the hopes that White cannot find a way to practically exploit his weaknesses.} Kc7 22. Rd3 Qh5 23. Rb3 b6 24. Ra3 a5 25. Rad3 Rg7 26. h3 Rf7 27. R1d2 Rfd7 28. a4 Rf7 {having achieved a strong defensive setup, Black shuffles his rook while White attempts to break through.} 29. Rf3 Rfd7 30. Rfd3 {Twofold repetition.} Rf7 31. b3 {White can afford to make small improvements and move closer to the time control, as Black has no threats.} Rfd7 32. Nf3 {now White starts to marshal his forces, returning the knight from the rim.} Qf5 33. Re2 Rf7 34. Rde3 Rdf8 35. Qxf5 {White decides to head for the endgame and pick up a pawn in the process.} (35. Nxe5 $6 {does not work due to} Qxf2+ 36. Rxf2 Rxf2+ 37. Kg1 Rf1+ 38. Kh2 R8f2+ 39. Qg2 Rxg2+ 40. Kxg2 Rf5 $11) 35... exf5 36. Nxe5 Rg7 37. f4 h5 38. h4 Rfg8 39. Rd3 Re8 40. Rde3 Rge7 41. Kf3 Re6 42. Rd3 {this deliberately invites the exchange on e5.} Bxe5 43. Rxe5 Rxe5 44. fxe5 Rxe5 {White has given back the pawn in return for a dominant king.} 45. Kf4 Re4+ 46. Kg5 Rd4 47. Re3 Kd6 $2 {Houdini (via the Frtiz interface) gives this a question mark, as it facilitates White's win.} (47... Rg4+ {would allow Black to control the g-file and prevent the loss of both kingside pawns without compensation.} 48. Kxf5 ( 48. Kxh5 $6 Kd6 $14) 48... Kb7 $16) 48. Kxf5 $18 Kd7 49. Kg5 1-0

01 May 2013

Nakamura Plays the Slav (Annotated Game #93)

This game is from round 10 of the recently-completed FIDE Grand Prix tournament in Zug.  As Black, GM Hikaru Nakamura plays a line of the Slav that complements my repertoire and I therefore thought the game was worth studying.  The original game and analysis from GM Giorgi Margvelashvili can be found in this ChessBase news report.  From my point of view, Mameyadrov starts to go astray as early as move 6 and never manages to recover from his experimental opening, although the play is complicated.  It was interesting to see where Nakamura chose to alternately play tactically and solidly, which reveals something about practical decision-making at the chessboard.

This sort of game analysis is far from comprehensive, but it speaks directly to what I think is important for opening study and for general chess improvement.  Digging into games that interest you and seeing what decisions were made and why can only help your chess.

(This is reflected in the PGN database download as Annotated Game #93)

[Event "Renova Group Grand Prix 2013"] [Site "Zug"] [Date "2013.04.29"] [Round "?"] [White "Mamedyarov, Shakhriyar"] [Black "Nakamura, Hikaru"] [Result "0-1"] [ECO "D10"] [Annotator "ChessAdmin/Houdini"] [PlyCount "44"] [EventDate "2013.??.??"] [EventCountry "SUI"] 1. d4 d5 2. c4 c6 3. Nc3 {the last time Nakamura reached this position was in 2005, against...Mamedayarov, as it happens. That time Nakamura played ...Nf6 in response. The text move is more testing and less likely to transpose to another opening.} dxc4 4. e3 b5 5. a4 b4 6. Nce2 {this and Ne4 (the most played in the database) give this variation independent significance, otherwise the knight retreats to a2 and b1 are likely to transpose to variations from the mainline Slav with 5. e3. The text move is extremely rare and one of the two games in the database was a previous effort by Mameyadrov.} Nf6 {an obvious developing move which was not played in the other two games in the database.} (6... Qd5 {is also the standard response to Ne4, but in this variation it seems counterproductive, as the following game from Mameyadrov shows.} 7. Ng3 (7. Nf4 {seems very good for White.}) 7... Nf6 8. Be2 e5 9. Nf3 Nbd7 10. O-O Bd6 11. Nd2 c3 12. bxc3 bxc3 13. e4 Qe6 14. Nf5 O-O 15. Bc4 Nd5 16. Nf3 N7b6 17. Bb3 Ba6 18. Re1 Bc7 19. dxe5 {1-0 Mamedyarov,S (2733) -Brunello,S (2575)Porto Carras 2011}) 7. Nf3 Ba6 {is a common idea in the variation, assisted in this case by the Ne2 blocking the Bf1.} 8. Ng3 c5 { a thematic counterblow in the center. Black should be happy to exchange queens on d1 following dxc5, stranding White's king in the center.} 9. Bd2 {this seems harmless, but Houdini already shows a half-pawn advantage for Black with the game continuation.} (9. Ne5 $5) 9... e6 10. Rc1 Qd5 {now White is not in a position to challenge the queen and the Ng3 looks misplaced.} 11. Ne5 {this appears weaker now than on move 9, with more of Black's forces already mobilized.} (11. dxc5 Nbd7 12. Bxb4 Nxc5) 11... cxd4 12. Nxc4 Nbd7 (12... dxe3 {would instead give White a little breathing room for development, for example} 13. Nxe3 Qb7 14. Be2) 13. Be2 {a tricky move. The g2 pawn is protected tactically from immediate capture, although is not fully immune.} (13. exd4 Qxd4 14. Be2 {would be a simpler way to proceed.}) 13... Rc8 {the solid choice, among other things avoiding the potential skewer on the h1-a8 diagonal. As noted below, ...Bxc4 does in fact work, but a good deal of calculation is required to confirm that.} (13... Qxg2 $2 14. Bf3 {and Black loses material to the bishop fork.}) (13... Bxc4 14. Bxc4 (14. Rxc4 d3 15. Qc1 {sets a trap, as Black is too weak on the back rank to take the Be2 immediately, but he can still defend well.} Rd8 (15... dxe2 $2 16. Rc8+ Rxc8 17. Qxc8+ Ke7 18. Bxb4+) 16. Bf3 Qa5) (14. Bf3 dxe3 15. Bxd5 exd2+ 16. Qxd2 Bxd5 {and Black has 3 pieces (including the two bishops) and a pawn for queen.}) 14... Qxg2 {is possible, with Black able to avoid punishment.} 15. Bb5 Rd8 16. Bc6 Qh3 17. exd4 Bd6) 14. Bf3 Qc5 15. b3 (15. Na3 $2 {initially looks appealing, opening up on the Qc5, however after} bxa3 16. Rxc5 Nxc5 {the material is more or less balanced, but Black has too many threats, including .. .Nd3+ and ...a2.}) 15... Be7 (15... d3 $5) 16. Ne2 $6 {the knight returns from its exile on g3, while continuing to use up White's tempi.} (16. O-O {seems logical.}) 16... d3 { this now gains another tempo with an attack on the knight.} 17. Nf4 O-O (17... Qc7 {is Houdini's choice, which would allow Black to defend the b4 pawn after . .. Qb8. Nakamura prefers to play more aggressively and not worry about the pawn.}) 18. Nxd3 Qf5 {Black has a lead in development, allowing him to initiate threats. Meanwhile White has not yet castled and his knights continue to be a source of problems.} 19. e4 $2 {this essentially gives away a pawn.} ( 19. Nxb4 Bxc4 {necessary to break up the strong pawn formation.} 20. Rxc4 (20. bxc4 Ne5 {and Black can effectively exploit his open lines and White's lack of piece coordination, for example} 21. O-O Rfd8 22. c5 Nxf3+ 23. gxf3 {Qxf3 is impossible due to the hanging Bd2} a5 24. Nc2 Qh3 $19 {with a powerful attack coming on White's king.}) 20... Rxc4 21. bxc4 Bxb4 22. Bxb4 Rb8 23. e4 Qe5) 19... Nxe4 20. g4 Qd5 {this defends the Ne4. Memedayarov perhaps miscalculated and thought that he could capture on b4 and drive off the queen.} 21. Qe2 (21. Bxb4 Ne5 $1 22. Ndxe5 (22. Bxe7 Nxd3+) 22... Bxb4+) (21. Nxb4 Qd4 22. O-O Nxd2 23. Nxa6 Ne5) 21... f5 {and White can bring no more pressure to bear on the Ne4.} 22. O-O Rxc4 {and White resigned, evidently not in the psychological condition to continue fighting uphill.} (22... Rxc4 23. bxc4 Bxc4 24. Nxb4 { a tricky resource for White.} Bxe2 (24... Bxb4 25. Rxc4 Bxd2 26. Bxe4 fxe4 27. Rxe4 $15) 25. Nxd5 exd5 26. Bxe2 Nxd2 27. Rc7 Rd8 28. Bb5 Bd6 29. Rxd7 Bxh2+ 30. Kxh2 Nxf1+ 31. Kg2 Rxd7 32. Bxd7 Nd2 33. Bxf5 Kf7 $17) (22... Ndc5 { is Houdini's preference.} 23. Nxc5 Bxc5) 0-1