25 December 2020

Commentary: 2020 U.S. Championship, Round 6 (Nakamura - Liang)

The next commentary game, from this year's U.S. Championship, made something of a sensation at the time, given the upset by Black. It shows the strengths of the Caro-Kann Classical and how Black can play sound positional chess and punish White if he is too aggressive. There are a number of other insights that can be gleaned from both sides' decision-making throughout the game, so this was a valuable one to review in detail. 

[Event "U.S. Championship"] [Site "Online"] [Date "2020.10.27"] [Round "6.1"] [White "Nakamura, Hikaru"] [Black "Liang, Awonder"] [Result "0-1"] [ECO "B19"] [WhiteElo "2829"] [BlackElo "2397"] [Annotator "ChessAdmin/Komodo 13.2"] [PlyCount "113"] [EventDate "2020.??.??"] [WhiteTeam "United States"] [BlackTeam "United States"] [WhiteTeamCountry "USA"] [BlackTeamCountry "USA"] 1. e4 c6 2. d4 d5 3. Nc3 dxe4 4. Nxe4 Bf5 5. Ng3 Bg6 6. h4 h6 7. Nf3 e6 { this move-order with an early ...e6 can have independent significance, or transpose back to the "main" main line Caro-Kann. Usually Black plays ...Nd7 here, to prevent Ne5.} 8. Bd3 {this early bishop development deviates from White's standard ideas of h4-h5 or an immediate Ne5. However, in many lines it is normal for White at some point to exchange off the light-square bishop and develop the queen.} Bxd3 {there is no good alternative to exchanging bishops.} 9. Qxd3 Nf6 10. Bf4 Qa5+ {this is the standard reply to the Bf4 development. Black asks White if he wants to maintain the bishop on f4, in which case the c-pawn will have to block the check, or if the bishop will give up its more active placement on f4 and retreat to d2.} 11. c3 Be7 {developing the bishop before the b8-knight, but this seems reasonable, since there is no other good square for it. Liang by doing this gives himself some additional options with the knight, beyond going to d7.} (11... Qa6 {is another idea, but may be more drawish.}) 12. Nf1 $146 {this (new) idea is to redeploy the knight and advance with g2-g4, while leaving the king in the center. While the idea of attacking down the g-file is now standard in some variations, this is an accelerated version of it. White does not seem quite ready to back it up, however.} c5 { Black is able to play this thematic break while his own king is still in the center, since White has no way of taking advantage of it. The light-square bishop is off the board, Black's Qa5 prevents White's queen from using the f1-a6 diagonal, and White's own king is still in the center as well.} 13. N1d2 Qa6 {...O-O and ... cxd4 also look like good options here. The text move pressures White to exchange queens, which is difficult to avoid.} 14. Nc4 { White blocks the queen trade, but at some positional cost. White's queen is now hanging, it is useful to observe, and the Nc4 will also have to be protected.} O-O 15. g4 $6 {White is not as well positioned to back up this kingside aggression as in other lines. Liang nevertheless chooses to avoid taking the g-pawn, which would open up the file.} Nd5 $15 {this is a solid move, anticipating g4-g5 and hitting the bishop.} (15... Nc6 {is recommended by the engines, who have no problem taking the g-pawn in the subsequent variations. White maintains material equality, but Black ends up with an edge.} 16. dxc5 (16. g5 Nh5 17. Bd2 cxd4 18. gxh6 dxc3 19. Bxc3 Nb4 20. Bxb4 Bxb4+ 21. Kf1 Rad8 22. Qe2 g6 $17) 16... Nxg4 17. Rg1 f5 18. Bd6 Bxd6 19. cxd6 Rad8 $17) 16. Be5 (16. Bg3 $5 {is the engine recommendation, preserving the bishop and staying solid on the kingside, but solidity was not Nakamura's original intent with g2-g4.}) 16... Nc6 {Black develops the knight, connects the rooks, and hits the bishop all at once.} 17. g5 h5 {another solid option for defense, reducing the complexity and number of targets for White to go after.} (17... f6 $5 {would be the way to take advantage of White's exposed bishop. For example} 18. gxh6 Nxe5 19. dxe5 Nf4 20. Qe4 Ng2+ 21. Kd1 (21. Ke2 $4 f5 {and the Nc4 is lost.}) 21... f5 $17) 18. g6 $2 {White decides to go all in and try to continue the attack, but Black is now winning. The engines point out the least worst variation, which however would have meant no more dynamic play for White and a solid positional advantage for Black.} (18. dxc5 Bxc5 19. Bg3 $15) 18... cxd4 {despite the pawn thrust, White is not in fact urgently threatening anything on the kingside, so Black can go ahead and start his own counterplay. The text move undermines e5 and starts opening lines for Black's pieces.} 19. Nxd4 (19. cxd4 $2 fxg6 20. Qxg6 Nxe5 $19 {and White has too many open lines to his king.}) 19... Nxd4 {Liang again chooses a more straightforward option, reducing material on the board before proceeding with his ideas.} (19... Rac8 $5 {could be played immediately, but is a more complex line.}) 20. Qxd4 (20. Bxd4 Nf4 21. gxf7+ Rxf7 22. Qf1 Bf6 $19) 20... Rac8 {pressuring the weak Nc4 and controlling the squares on the half-open c-file.} (20... fxg6 $19 {also looks very good.} 21. Bxg7 $2 Rf4 $19) 21. Ne3 Bc5 22. Qe4 Bxe3 {an exchange that reduces White's attacking capability and gives him an isolated e-pawn.} 23. fxe3 fxg6 (23... f6 $5 {would seal off the kingside for good.}) 24. Bd4 ( 24. Qxg6 Rf7 25. Bd4 Ne7 26. Qe4 (26. Qxh5 Nf5 27. Qe2 Qa5 $19 {preparing ... e5.}) 26... Nf5 $17) 24... Rf5 $19 {blocking the attack on g6 and preparing to double rooks. Black is now a pawn up and has much better piece placement and coordination. In particular, the Bd4 is centralized but blocked in and White has to worry about ...e5.} 25. a3 {preparing to castle, but weakening the light squares further.} Rcf8 (25... Kh7 $5 {to protect the g-pawn and free up the Rf5.}) 26. O-O-O Kh7 27. Rhg1 Nf6 {Black is now able to powerfully reposition the knight and cut off any attacking possibilities down the g-file.} 28. Qc2 Ng4 29. e4 Rf1 {Black would be happy exchanging on f1.} 30. c4 R1f3 { here the engines prefer simply exchanging down, given Black's material and positional advantages.} 31. e5 Rc8 {switching targets and prompting White's next move, which unblocks the f1-a6 diagonal and further blocks in the White bishop.} 32. c5 Rcf8 {Liang is not in a rush to press his advantage, possibly due to time control considerations. Several other possibilities exist to make progress.} (32... Rd8) (32... b6) (32... Rh3) 33. Kb1 Rf1 34. Ka2 Rxd1 { now Black goes for the simplifying exchange.} 35. Rxd1 Rd8 {Black's good knight vs. bad bishop situation is now even more clear on the board, along with his material advantage. Although he has doubled g-pawns, later he can get rid of them and have strong passed pawn(s) on the kingside.} 36. Rd2 Qc6 { physically blockading the c-pawn and moving to the more central diagonal.} 37. b4 Rd5 38. Bc3 Ne3 {the engines agree with this idea, which passes up taking the e-pawn in favor of a more dominating central position for Black.} (38... Nxe5 39. Qd1 Rxd2+ 40. Qxd2 $19 {still leaves Black with an advantage, but White has more mobility and the road to victory would likely be harder.}) 39. Qc1 Nf5 40. Qe1 {protecting the h4 pawn, although Black can win it by force if he chooses.} Rxd2+ 41. Bxd2 Qd5+ {comparing this position with the above variation, it's clear that Black's pieces are more dominant.} 42. Kb2 Qd3 ( 42... Nxh4 $5 {apparently Liang did not want to go into a pure queen ending, even two pawns up.} 43. Qxh4 Qxd2+ $19) 43. Bg5 Nd4 44. Qc3 {protecting against further queen penetration. Black now picks up the e-pawn, however.} Qe2+ 45. Kb1 Qxe5 46. a4 {White is desperately seeking counterplay at this point, trying to mobilize the queenside pawn majority.} a6 {the simple way to restrain White's pawns.} 47. Kb2 Qe2+ 48. Qd2 Qe4 {leaving the way open in front of the e-pawn and laterally pressuring the h-pawn, keeping the bishop tied to its defense.} 49. Qc3 e5 50. Qc4 Qg2+ 51. Kb1 Qc6 {using the full power of his queen to influence both sides of the board.} 52. a5 {now Black fully dominates the light squares and White cannot hope to make progress.} Nb5 53. Kc1 Qh1+ 54. Kd2 Nd4 55. Qd3 Qg2+ 56. Kc3 Qa2 {threatening to mate on b3.} 57. Qd1 {White apparently saw the b-pawn would now fall anyway after ...Nb5+ and subsequent Black queen checks, so the game is over.} 0-1

05 December 2020

Videos completed: "Why You Should Study Master Games" by Tatev Abrahamyan


"Why You Should Study Master Games" (parts 1 and 2) are the final videos in the Chess.com series by Tatev Abrahamyan. I've made a point of periodically doing "commentary" annotated games of master (usually GM) level games on this blog, including collecting them in a PGN database available for download on the sidebar link; I posted some previous thoughts on the process in "Analyzing master games for training".

Part 1: Abrahamyan introduces the video with the observation that by studying master games, we will see more ideas and also be able to avoid known mistakes, thereby not having to reinvent the wheel in our own games. Studying historical games therefore is relevant for today's training.

The first example game given is Capablanca - Treybal, in an inferior Stonewall type position for Black. Capablanca fixes the pawn structure and then, as is common in closed positions, can take his time to organize pawn breaks and put his pieces on optimal squares to make progress. Also illustrated are the benefits of a space advantage and White's avoidance of exchanging pieces, which would just make Black's life easier.

The second game is Petrosian - Ledic. The structure is very similar, but without queens on the board. Black gets frustrated and loses more quickly than necessary, but White could have won in any case, with his ability to play on both sides of the board and target Black's weaknesses faster than they could be defended.

Part 2: the theme of modern relevance is continued, with the first example game being again from Capablanca and the second from Carlsen. Capablanca manages to win an even-looking double rook ending, by staying patient and flexible and working to provoke weaknesses, using a minority attack on the kingside to open up the h-file for a rook. 

The second example game is Radjabov-Carlsen from 2012. The structure is again very similar, with the addition of light-squared bishops on both sides. Black wins the endgame using a strategy reminiscent of Capablanca's.

I found the examples useful in both video parts, which together total around 20 minutes, but I felt the broader theme was treated rather perfunctorily. To do it properly, though, would take a lot more content.

12 November 2020

Commentary: 2019 National Open, Round 5 (Ramirez - Sorokin)

This next commentary game is a nice example of how strategic, positional play in the English Opening can lead to a tactical finish, sometimes rather quickly. With these master games, I save interesting ones periodically and then get to them whenever I can. GM Alejandro Ramirez recently had a disappointing 2020 U.S. Championship, so I decided now would be a good time to look more deeply at this instructive and clean win of his over FM Aleksey Sorokin, as compensation. (Original ChessBase report and analysis on the 2019 National Open from Li Ruifeng can be found here.)

[Event "National Open 2019"] [Site "Las Vegas USA"] [Date "2019.06.14"] [Round "5"] [White "Ramirez, Alejandro"] [Black "Sorokin, Aleksey"] [Result "1-0"] [ECO "A29"] [WhiteElo "2574"] [BlackElo "2536"] [Annotator "ChessAdmin/Komodo 13.2"] [PlyCount "51"] [EventDate "2019.??.??"] 1. c4 Nf6 2. Nc3 d5 {this simplifies White's opening choices, as it makes little sense not to exchange the c-pawn for Black's central d-pawn.} 3. cxd5 Nxd5 4. g3 {the most popular continuation. The more flexible Nf3 also scores as well, around 57 percent in the database.} e5 {staking out territory in the center (which Nf3 would have prevented).} 5. Bg2 {forcing Black to choose what to do with the Nd5.} Nb6 {preferred and best scoring option (around 50 percent) .} 6. d3 {still avoiding committing the other knight. Moving the d-pawn seems necessary in any scenario for White.} Be7 7. Be3 {the bishop development to e3 is a standard idea in some lines of the English. Here, f4 and g5 are out and d2 would be more passive. The Black king's knight is also on b6 rather than f6 as normal, so cannot harass it.} O-O 8. Rc1 {activating the rook on the half-open c-file.} Re8 9. Nf3 {the knight is finally developed.} (9. a3 { is often played here.}) 9... Nc6 {the e-pawn must be protected.} 10. O-O Bf8 { overprotecting the e-pawn and choosing to give the bishop a defensive role on the kingside, which is lacking the usual protection of a knight.} 11. a4 { White has played a variety of moves here. Normally one would expect an a-pawn thrust to be more consistent with a White rook on a1. One recent high-level alternative:} (11. Bg5 Qd7 12. a3 h6 13. Bd2 Qd8 14. Ne4 a5 15. Nc5 a4 16. Qc2 Ra7 17. Rfe1 Nd4 18. Nxd4 exd4 19. e4 dxe3 20. Bxe3 c6 21. Ne4 Be6 22. Bc5 Ra8 23. Bxf8 Rxf8 24. Nc5 Bc8 25. Re4 Re8 26. Rce1 Rxe4 27. Rxe4 Ra5 28. h3 Kf8 29. d4 Ra8 30. Re1 g6 31. Qd2 Kg7 32. Qf4 Nd7 33. Ne4 Ra5 34. Nd6 Nf6 35. Re8 Qd7 36. Rxc8 g5 37. Qd2 Ra6 38. Qb4 c5 39. dxc5 Rxd6 40. cxd6 Qxc8 41. Bxb7 Qxh3 42. Qxa4 h5 43. Qd4 Qd7 44. Bf3 h4 45. gxh4 gxh4 46. Qxh4 Qf5 47. Kg2 Kf8 48. a4 Qg6+ 49. Qg3 Qf5 50. b4 Nd5 51. Qg4 Qe5 52. Qc8+ Kg7 53. Qg4+ Kf8 54. d7 Ke7 55. Qe4 Qxe4 56. Bxe4 Nxb4 57. Bf5 Nc6 58. Kf3 Kd6 59. Kf4 f6 60. Be4 Nd8 61. Kf5 Kxd7 62. Kxf6 Kd6 63. a5 Ne6 64. a6 {1-0 (64) Caruana,F (2835) -Nepomniachtchi,I (2784) chess24.com INT 2020}) 11... a5 $6 {Black blocks the a-pawn's further advance, but this was not currently threatened. Perhaps it was a deliberate invitation to exchange on b6 and give Black the two bishops, although White seems to inflict enough structural damage to more than compensate for that.} 12. Bxb6 (12. d4 $5 {is the engine line and actually has been played in a few games. The point is that exchanges on d4 favor White's piece activity.} exd4 (12... Nc4 {is what the engines give} 13. Nb5 Nxe3 14. fxe3 $14) 13. Nxd4 Nxd4 14. Qxd4 Qxd4 15. Bxd4 $16) 12... cxb6 13. Nb5 { now White has b5 as an excellent outpost for the knight.} Be6 {this seems to unnecessarily weaken the e-pawn, by blocking the Re8.} 14. d4 {now Black cannot maintain the pawn on e5.} e4 (14... exd4 {is the other option, which likely will lead to wholesale liquidation:} 15. Nfxd4 Bg4 16. Nxc6 bxc6 17. Bxc6 Bxe2 18. Qxd8 Raxd8 19. Bxe8 Bxf1 20. Kxf1 Rxe8 $11) 15. Ne1 {this is the most challenging option for White, avoiding a piece exchange and activating the strong Bg2. The knight will later emerge via g2.} (15. Ne5 {is less ambitious and gives Black more play.} Nxe5 16. dxe5 Qxd1 17. Rfxd1 Bb3 18. Rd4 Rxe5 $11) 15... f5 (15... Rc8 $5 {may be better, but is a typical complicated engine line.} 16. Bxe4 Nxd4 17. Rxc8 Bxc8 18. Qxd4 Qxd4 19. Bxh7+ Kxh7 20. Nxd4 $11) 16. f3 {a forcing move which causes Black to go wrong.} Bd5 $2 {this will allow White to force a favorable structure in the center.} (16... exf3 17. Bxf3 {and White should have a comfortable game after e2-e3 and Ng2, but the engine rates it as equal.}) 17. fxe4 fxe4 (17... Bxe4 {would give White too much of a free hand in the center.}) 18. e3 {White's d-pawn is now protected and passed, while Black's isolated e-pawn requires defending.} g6 {Black needs to activate his dark-square bishop.} 19. Bh3 {an illuminating move. White seizes a better diagonal for his bishop, as the e4 pawn is doubly protected. This leaves the Bh3 superior to its Black counterpart.} Bh6 (19... Be6 $2 {attempting to exchange bishops does not work tactically.} 20. Bxe6+ Rxe6 21. Qb3 Qe7 22. d5 $18) 20. Ng2 {getting the knight back into the action, protecting e3 and looking to go to f4. At this point White is strategically winning, as his pieces are all better placed than Black's.} Re7 21. Nf4 {this is not as forcing as some other possibilities.} (21. Rf6 $1 {is the engine move, which of course is not at all obvious. The point is that the rook threatens to go to d6, while White can also play Qg4 and Rcf1, mobilizing his heavy pieces to dominate.} Nb4 22. Qg4 $16) (21. Qg4 $5 {with the idea of Qh4 also looks very good.}) 21... Nb4 {protecting the Bd5 again.} 22. Qg4 Nd3 $4 {Black makes a bid for counterplay which fails to a tactic.} (22... Bxf4 {Black likely hesitated to give up the two bishops, even though it was best for defense.} 23. gxf4 $14) 23. Nxd5 Nxc1 (23... Qxd5 24. Rc8+ Rxc8 25. Qxc8+ Kg7 26. Qf8# { White's control of the f-file pays off.}) 24. Qh4 $1 {with a double attack on e7 and h6.} (24. Nxe7+ Qxe7 25. Nc3 {trapping the knight also should win.}) 24... Qxd5 (24... Bf8 {after the exchanges Black just ends up a piece down.} 25. Nxe7+ Qxe7 26. Qxe7 Bxe7 (26... Ne2+ 27. Kf2) 27. Rxc1) (24... Bxe3+ 25. Nxe3 Ne2+ 26. Kg2 $18) 25. Qxe7 Bxe3+ 26. Kh1 {White now threatens Be6+ with mate to follow.} 1-0

01 November 2020

Video completed: "Why You Should Never Underestimate Your Opponent" by Tatev Abrahamyan

"Why You Should Never Underestimate Your Opponent" is the ninth video in the Chess.com series by Tatev Abrahamyan. Keeping full awareness of all of my opponent's resources has been a struggle, so this topic is particularly important for me. It also reinforces the idea of focusing your play on the situation on the board, not making assumptions based on your opponent's rating.

The first example game is FM Anastasia Avramidou - GM Valentina Gunina, from the 2018 Olympiad. White was outrated by around 200 Elo. Black plays a careless move in the opening, with the apparent intent of avoiding a simplifying line, and White in response find a tactical sequence that picks up an unprotected rook. 

The second one is GM Sergey Fedorchuk - GM Andreas Kelires. At the time, Kelires was not yet a GM and White had around a 600 Elo advantage. The opening is a Najdorf Sicilian and follows an aggressive line with opposite-side castling. White trusts his attack too much and ignores how Black can turn the tables, defending his king position while making multiple threats.

The last example is GM Fabiano Caruana - GM Zviad Azoria, from the 2018 U.S. Championship. White had around a 200 Elo advantage and it was a good year for Caruana, so perhaps he felt he could/should win. In this particular case, however, a very equal R+N+pawns endgame was reached. Caruana passes up a chance to wrap up the draw and tries for an unbalanced pawn race position. Instead, he ends up a pawn down in a lost knight ending after the rooks and other pawns are exchanged.

The common thread in all of these is the negative consequence of relaxing your guard and not worrying about what your opponent can do. This is never good practice, even if your rating is higher than your opponent's.

21 October 2020

Video completed: "Why You Should Always Muddy the Waters When Losing" by Tatev Abrahamyan

"Why You Should Always Muddy the Waters When Losing" is the eighth video in the Chess.com series by Tatev Abrahamyan. This is an excellent practical idea, both for while you are at the chessboard and to keep in mind during post-game analysis of your own games. You do not in fact get any points for losing more correctly, as the engine analysis scores of your games might imply. So to give yourself a chance to turn the game around - which means giving your opponent more chances to blunder - you may need to take more risks, in order to make your opponent's path to victory less clear. Specifically, this involves trying to generate the possibility of some counterplay, in order to complicate the situation. (This idea is also closely allied to the art of swindling.)

The first example is from a classic game, Amos Burn - Frank Marshall. Marshall, in trouble, gave up a rook on a8 (which wasn't doing anything anyway) in order to open up the center and further expose White's king. Black is lost in the long term, in terms of counting material, but moves in the short term from defender to attacker and effectively takes the White queen out of the game. Abrahamyan points out that for psychological reasons, these kinds of inflection points in games can sometimes trigger immediate blunders, since your opponent will have trouble adapting to the new situation and mentally switching gears.

The second example is GM Nana Dzagnidze - GM Marie Sebag, from the 2019 Cairns Cup. Here Black's position is "miserable", with one bishop completely out of the game in the corner and the other not doing much, with White about to penetrate on the queenside threatening to win a pawn. Instead of opting for static defense and continued positional torture, Black sacrifices a knight for two center pawns, immediately giving her excellent control of central space and activating her two bishops. Again, White goes from attacker to defender and has to completely rethink things. In the actual game, White eventually won, but as Abrahamyan puts it, Black was at least alive for much longer and was playing for three results rather than just two (loss or draw, with no counterchances).

The last example is IM Davaademberel Nomin-Erdene - GM Irina Krush (the video graphic intro reverses the order, although the audio makes it clear Krush has the Black pieces), from the 2018 Olympiad. Black is up a pawn, but similar to the previous example she has a bishop locked away at a8 and White is bearing down on the queenside, this time with two advanced connected passed pawns. Black (according to post-game discussions) felt she had messed up the game and just making natural moves would lose. Black pitched a pawn to try and gain activity, which gave White the opportunity to capture it with the wrong piece. Because of this, Black was able to sacrifice a second pawn, opening up her bishop on the long diagonal and getting her queen into a kingside attack, after which White blundered under pressure.