25 March 2019

Commentary: Dortmund 2017, round 1 (Kramnik - Fedoseev)

Continuing with the commentary theme of the Caro-Kann Exchange variation at the super-GM level, the below game is from the first round of Dortmund 2017, featuring Kramnik as White. He makes a non-standard choice of 6. Na3!? which leads to some unbalanced play and a clash of ideas in the middlegame. Black (Fedoseev) deliberately leaves his king in the center and weathers a White attack with some classic Caro-Kann themes, including the half-open e-file and sacrifice on e6. Black's cool nerves give him the victory in the end.

[Event "45. Sparkassen Chess-Meeting"] [Site "Dortmund"] [Date "2017.07.15"] [Round "1"] [White "Kramnik, Vladimir"] [Black "Fedoseev, Vladimir"] [Result "0-1"] [ECO "B13"] [WhiteElo "2812"] [BlackElo "2726"] [Annotator "ChessAdmin/Komodo 11.2"] [PlyCount "58"] [EventDate "2017.??.??"] 1. e4 c6 2. d4 d5 3. exd5 cxd5 4. Bd3 Nc6 5. c3 Qc7 {immediately seizing the b8-h2 diagonal. Remarkably, Black has a plus score in all variations after this in the database.} 6. Na3 {a rare continuation, but with precedent.} a6 { essentially forced, in order to keep White out of b5. One could argue that the time-wasting moves cancel each other out in terms of tempi, but I would say that ...a6 is more useful to Black than White's knight moves are for him.} 7. Nc2 {where else?} Nf6 8. h3 {now White considers it best to prevent a future pin on f3 after ...Bg4, as Be2 would be a time-wasting retreat. Ne2 has also been played here.} e6 {shutting in the Bc8, but now there's nowhere for it to go on the kingside.} 9. Nf3 b5 {making room for the bishop on the queenside.} 10. O-O Bb7 {while it doesn't look well-placed here, in fact the bishop is able to influence the e4 square to good effect.} 11. Re1 Bd6 {the most dynamic option for bishop development. Black reinforces his control of the b8-h2 diagonal and doesn't worry about Bg5, which under other circumstances would be annoying. However, there is a tactical reason why it's not best for White, as we'll see.} 12. Bg5 (12. a4 {played immediately is what the engines recommend.} bxa4 13. Rxa4 O-O 14. Qe2 Ne7 15. Bxa6 Qb6 16. Bb5 Rxa4 17. Bxa4 Ba6 18. Qd1 Ng6 $11 {with compensation for the pawn. White's Ba4 is out of the action and Black's minor pieces are all better than their counterparts, while Black also is much better positioned to take advantage of the open a-file.}) 12... Ne4 $1 13. a4 (13. Bxe4 dxe4 14. Rxe4 h6 15. Bd2 Na5 16. Re1 Nc4 $11 {and again Black has compensation for the pawn, based on his superior piece placement and scope. The two bishops in particular are very nice in this position.}) 13... bxa4 $5 ( 13... O-O {is a pawn sacrifice that the engines evaluate as dead even.} 14. axb5 axb5 15. Bxb5 Rxa1 16. Qxa1 h6 17. Be3 Ra8 18. Qc1 Na5 $11 {The two bishops and Black's dominating piece play provide full compensation for the pawn. However, I can understand how Fedoseev might not think that the best course in the long run, given White's extra passed b-pawn.}) 14. c4 {it appears here that Kramink didn't want to go down the road of capturing on e4 or a4, which did not promise more than equality. White also hopes to take advantage of Black's uncastled king position.} (14. Bxe4 dxe4 15. Rxe4 h6 16. Bc1 Ne7 17. Re1 O-O $11) (14. Rxa4 h6 15. Be3 O-O $11) 14... Nxg5 15. Nxg5 dxc4 {otherwise cxd5 is threatened, with a pin on the e-pawn.} (15... Be7 {is an interesting alternative.} 16. Qh5 Bxg5 17. cxd5 Ne7 18. Qxg5 Bxd5 {is evaluated as equal by Komodo, with White now choosing among various ways of recapturing a pawn. However, it's not much fun to play as Black, with your king in the center and your opponent having open lines and initiative.}) 16. Bxc4 {White has sacrificed a pawn for open lines and an attack. The half-open e-file and sacrificial possibilities on e6 are classic Caro-Kann themes for white.} Nd8 $5 {visually this seems rather strange, retreating the knight and leaving the king in the center, but perhaps gives better chances for Black than the alternative.} (16... O-O {is a rather difficult line for Black, with a narrow path to holding the game.} 17. Qh5 h6 18. Nxe6 fxe6 19. Rxe6 Bh2+ 20. Kh1 Rf7 21. Ne3 Nxd4 22. Rb6 Raf8 23. Rxh6 gxh6 24. Qg6+ {with a perpetual check}) 17. Ne3 {bringing the knight into the attack, although this does let Black exchange off a piece.} Bf4 (17... h6 18. Nf3 O-O $11 {might be a simpler approach.}) 18. Qh5 $2 {White apparently misses Black's available defensive resources. This however is the most natural-looking move, bringing the queen into the action.} (18. Qxa4+ {regains the pawn and is evaluated as equal, although a long dance of the pieces ensues.} Bc6 19. Nd5 Qd7 20. Qa5 Nb7 21. Qa2 Bxg5 {to prevent the knight sac on e6. So far it's all been normal moves, but more complicated calculation and evaluation would be necessary to see it through.} 22. Nb6 {White's only move that doesn't lose} Qxd4 23. Nxa8 O-O { and now for example} 24. Qxa6 Bh4 25. Qxc6 Bxf2+ 26. Kh1 Bxe1 27. Qxb7 Bg3 { looks like an eventualy draw, but it's an imbalanced (albeit evaluated as equal) position.}) 18... Bxe3 $1 {removal of the guard of the Bc4.} (18... Bxg5 $6 {is inferior, giving White a reasonable game after} 19. Qxg5 O-O) 19. Rxe3 Qxc4 20. Rxe6+ Kf8 {this move requires steady nerves, but is the best. White can no longer make progress.} (20... Nxe6 21. Qxf7+ Kd8 22. Nxe6+ Kc8 23. Qxg7 Re8 $17 {still ultimately in Black's favor, but White is a lot more active.}) 21. Re5 h6 {well calculated by Fedoseev, the only move that wins. Once the knight is pushed back and Black follows with ...g6, his king is safe.} 22. Rae1 g6 23. Qh4 Kg7 $19 24. Nxf7 {a last, desperate attempt on the king. White does not have enough material left to successfully attack, however.} Nxf7 25. Re6 { with the threat of Qf6+} g5 {another instance of cold-blooded calculation.} 26. Qh5 {the queen is now headed to g6.} Rhe8 27. Qg6+ Kf8 {leaving White with no more threats, as the Nf7 holds the position.} 28. f3 Qxd4+ 29. Kh1 Rac8 0-1

22 March 2019

Book completed: How Chessmasters Think

I recently completed How Chessmasters Think by IM Paul Schmidt, who was a strong Estonian player in the Paul Keres era and subsequently emigrated to the United States.  I ran across the book largely by accident a while ago and got it on Kindle, it being hard to find otherwise.  It's rarely referred to in chess improvement literature, but the subject matter seemed to be very relevant.

Rather than a tutorial on how chess players should think, the book is more of a descriptive exercise in how master-level players do think during a game, both on a theoretical and practical level.  The author presents a series of annotated games, but rather than talking about the ideas or giving analysis in the usual method, instead writes annotations based on an imagined thinking process for each player.  Essentially, he answers the question "why did the player choose this move" with a thought experiment for both sides of the board.  Periodically he will also introduce an objective voice (the "critic") when critical moves are overlooked by both players.

I found several advantages to the author's approach and learning benefits from the content.
  • Some clear and valuable explanations of specific strategic considerations in main line openings, especially relatively early choices, which all too often are skipped over.
  • Each of the chapters has a theme regarding chess situations and judgment which can be generalized, at least to some extent, in terms of facing similar future decisions.
  • The games themselves are varied and high-quality, with frequent appearances by world-class players such as Keres, Alekhine, and Euwe, along with games involving Botvinnik, Fine and Capablanca.  Some lesser master games are also included that are relevant and interesting, by people known to the author.
  • The combination of strategic and tactical considerations as part of each side's "thought process" emphasize the practical aspect of thought, rather than pure strategy or tactics, as is often presented.
A couple things were less helpful, from my perspective.
  • A few move typos are scattered throughout the book, in both the game score and given variations.  Most of the time it's clear what the move should be (for example Nc5 instead of Ne5), but in one or two spots it was really head-scratching.  I expect this was due to the Kindle OCR conversion process.
  • The author has the tendency to include 2-3 pages of variations of 8-10 moves and stream-of-consciousness thought in the early middlegame, which make it difficult to keep following the thread.  He admits late in the book that most chess masters will calculate 3-4 moves ahead in non-forcing situations, but that it is necessary to go further when necessary.  So the stream-of-consciousness over the length of a long variation sometimes comes across as a bit artificial.  On the positive side, the moves then play out as part of the game, which makes it much easier to understand what is actually going on.
  • While it's good to have to work things out for yourself, I found some annotations and explanations cut off a bit prematurely or were of the "...and wins" variety, when it wasn't immediately clear why it would win (eventually).  The author seems to have been assuming an advanced (around master-level) audience in those cases.
I would say that players around Class B and up would benefit from the book, which isn't terribly long (16 chapters / games).

18 February 2019

Commentary: Tata Steel 2019, Round 2 (Duda - Van Foreest)

Today's commentary game naturally follows from the earlier Tata Steel 2019 Round 1 game. Van Foreest (on the White side of a Caro-Kann Exchange) lost the earlier struggle against Anand, but then became a winner on the Black side of the same opening. This game is quite different, though, as White's early choice to vary his development scheme sends Black down a more classical path, instead of Anand's setup featuring an open g-file and opposite-side castling.

Some key takeaways from the game, for Caro-Kann players and in general:
  • The benefit to Black of exchanging light-square bishops
  • Conditions for being able to defend against White's ideas for pressure on the h-file
  • The key role of queenside counterplay (see moves 23-25) so as to not give White a free hand on the kingside
  • The recurrence of tactical ideas such as Ne4-d2, which eventually becomes decisive for Black
  • How either player could have chosen to go for a drawing line (perpetual) at different times

[Event "81st Tata Steel Masters 2019"] [Site "Wijk aan Zee"] [Date "2019.01.13"] [Round "2"] [White "Duda, Jan-Krzysztof"] [Black "Van Foreest, Jorden"] [Result "0-1"] [ECO "B13"] [WhiteElo "2738"] [BlackElo "2612"] [Annotator "ChessAdmin/Komodo 11.2"] [PlyCount "100"] [EventDate "2019.??.??"] 1. e4 c6 2. d4 d5 3. exd5 cxd5 4. Bf4 {an alternative try to the usual Bd3. White accelerates his seizure of the h2-b8 diagonal and does not let Black's queen get to c7.} Nc6 5. c3 Nf6 (5... Bf5 {is in alternative way to play, anticipating the Bd3 development by White and looking to exchange off bishops early. In the game, this happens much later and also results in a change of Black's kingside pawn structure.}) 6. Nd2 {the second most popular move in the database. White prepares to support Ngf3 after Black's next.} Bg4 7. Qb3 { a normal reaction by White, once the bishop ceases protecting the b7 pawn.} Qc8 {this is less committal than the alternative ...Na5.} 8. Ngf3 e6 9. Bd3 (9. Ne5 $5 {is an interesting idea here, but simply retreating the bishop to f5 seems to take any sting out of it.} Bf5 $11) 9... Bh5 {a relatively rare option, with ...Be7 being standard. The idea here is to retreat to g6 and exchange off the Bd3, which otherwise is well-positioned to target Black's kingside.} 10. O-O Bg6 11. Bxg6 {Komodo, in contrast to some other engines, assesses that it is better for White to not exchange on g6. For White, often the idea behind this exchange is to create a target for an h-pawn thrust, which is what in fact occurs later on.} hxg6 12. Rae1 {committing to a central/kingside strategy.} Be7 $11 {Taking stock of the position, Black has full equality. The light-squared bishop exchange has left Black solid on the kingside and White has no obvious advantage, although he can try for play on the h-file, as in the game. Duda's next move is a novelty in the database and was likely an attempt to introduce some uncertainty into the position, while again looking for chances on the h-file.} 13. g3 $146 {as we will see later, the idea of this move is to prepare the pawn thrust h2-h4.} (13. Ne5 {is a typical try by White that scores well in the database (67 percent), but should not objectively be a concern to Black. The database figures also seem to be skewed by lower-rated games.} Nxe5 14. dxe5 Nd7 {similar to the game continuation looks fine for Black.}) 13... O-O {no reason to postpone castling.} 14. Ne5 Nxe5 {Black chooses to remove the well-placed central knight immediately. Although not forced, this is an excellent defensive idea, as otherwise White typically starts developing tactical ideas on the e-file to target the e6 pawn, with a knight sacrifice a possibility later on g6 or f7.} 15. dxe5 Nd7 16. h4 { White follows up on his earlier idea of g3. Should Black be worried? As the defender in this type of position, the usual assessment is that after two minor piece exchanges, Black should be all right, since the sacrificial possibilities by White are limited. White will also need time to bring his other pieces to bear on the kingside.} Nc5 {puts the knight on its best square, kicking the queen and eyeing e4 and d3.} 17. Qc2 Qc6 {putting the queen on the long diagonal and improving its mobility. Now White's lack of a light-squared bishop to oppose it is highlighted.} (17... b5 {is what the engines like in this position, following up with ...Qb7 to put the queen on the long diagonal and give black the option of a minority attack on the queenside.}) 18. Re3 { this just ends up being awkward for White and wasting time. Presumably the idea was to eventually transfer the rook along the third rank.} (18. Nf3 $5) 18... Qa6 {pressuring the a-pawn and also placing itself on another useful diagonal.} 19. Qb1 {with this move, it's clear that White no longer has the initiative and must start responding to Black's threats.} Rac8 20. Kg2 { needed to clear the first rank for his rook to shift to h1.} b5 {now Van Foreest plays the pawn advance, gaining space and with the eventual idea of a minority attack along with the a-pawn.} 21. Bg5 Qb7 {although Black has been moving his queen often, each time it has been with a purpose and has improved his relative position. This time is no different, as the queen will still be well-placed on e7 after the exchange of bishops, and the a-pawn is now free to advance.} 22. Bxe7 Qxe7 23. Rh1 a5 24. Qd1 b4 {Black's counterplay on the queenside balances White's play on the kingside.} 25. Qg4 (25. h5 {would amount to the same thing after} bxc3) 25... bxc3 {active defense.} (25... Qb7 $5 {is another interesting way to defend.} 26. h5 d4+ 27. Rf3 bxc3 28. bxc3 dxc3 29. hxg6 fxg6 30. Qxg6 Rf5 $11 {and White has nothing better than a perpetual.}) 26. bxc3 Rb8 {Black again correctly emphasizes counterplay, threatening to go to b2 with his rook.} 27. h5 g5 {Van Foreest goes for the option that is equal, but allows him to keep going in hopes of a win. The correct decision, as it turns out.} (27... Rb2 28. hxg6 fxg6 29. Qxg6 Rxd2 30. Qh7+ Kf7 {is a perpetual for White.}) 28. h6 g6 {this defensive idea should be well known to Caro-Kann players, to prevent a breakthrough on the h-file.} 29. Nf3 {targeting the weak g5 pawn, but} Ne4 {holds everything together for Black. } 30. Re2 {covering the second rank against the threat of ...Rb2. However, this leaves the c-pawn hanging.} Nxc3 31. Rc2 Ne4 32. Nd4 {although Black is a pawn up, now White gets to have equivalent play for it, gaining the initiative in compensation. The main threat here is the knight fork on c6.} Rbc8 33. Nc6 Qa3 {preserving the a-pawn.} 34. Rhc1 Kh7 {another important defensive idea for Black, blockading the h-pawn to prevent a future sacrifice on h7. The h-pawn is now a long-term liability for White, especially in an endgame, when Black opening the h-file by capturing the pawn will no longer be of consequence. Black does have to be careful to manage potential threats from any occupation of the f6 square by White, however.} 35. Qe2 {now Black has to take care of his Ne4, which is out of squares after a White pawn advances to f3. Previously it could have gone to d2, with the tactical idea of Rxd2 followed by ...Qxc1. The Qe2 instead now covers the d2 square.} g4 {Black gives back the material so his pieces regain freedom of movement.} 36. Qxg4 Rc7 37. Qf4 {this appears to be a try by White to maintain winning chances.} (37. f3 {leads to lines where Black can win the a-pawn, but his queen is too exposed to White's rooks for it to matter, so essentially White can get a perpetual on the queen.} Nd2 38. Rc3 Qb2 (38... Qxa2 {doesn't gain Black anything either} 39. R3c2 Qa3 40. Rc3 Nb3 $11) 39. R3c2 Qa3 $11 {with a repetition of position to follow, whether Black takes the a2 pawn or not.}) 37... Rfc8 $15 {obvious and good. Now White has to be careful about the Nc6, which has only one viable square (d4), as well as his currently under-protected rooks.} 38. g4 $6 {White likely underestimated the consequences of Black's next move.} (38. Qg4 Qd3 $15) (38. Nd4 {bailing out with the knight is likely the best (and most practical) option.} g5 {now has much less sting, since the g4 square is available for the queen.} 39. Qg4 Rxc2 40. Rxc2 Rxc2 41. Nxc2 Qf8 $15) 38... g5 $1 39. Qh2 (39. Qf3 Qxf3+ 40. Kxf3 f6 41. exf6 Nxf6 {and the h-pawn will fall after} 42. Nd4 Rxc2 43. Rxc2 Rxc2 44. Nxc2 e5 {first preventing the knight's return to d4} 45. Ne3 Kxh6 $17 {and Black (at the GM level) should be able to convert the endgame with his extra passed d-pawn.}) 39... Nd2 $19 {using the same tactical idea with the knight move to d2 as before, but now threatening ... Qf3+. By this point, White is essentially lost.} 40. Rc3 (40. Qg3 {is objectively better, but still leads to a lost endgame, so White tries something else.} Qxg3+ 41. Kxg3 Kxh6 $19) 40... Qa4 {the only winning move, threatening the g4 pawn. It's not too hard to find, though.} 41. Qh5 {protecting the pawn, but now Black's queen dominates in the center.} Qe4+ 42. Kh3 (42. f3 Qe2+ 43. Kg3 Nf1+ $19) 42... d4 {passed pawns must be pushed! Now White's position collapses all over the board.} 43. Rg3 ( 43. Qxg5 $2 Rg8 $19) 43... Qf4 {threatening the f2 pawn as well as ...Ne4 with a double attack on the rooks.} 44. Rd1 Ne4 {an elegant finish.} (44... Rxc6 { is straightforward, but perhaps required a bit more calculation. Or Black just preferred winning with the text move.} 45. Rxd2 Rc3 (45... Qxd2 $2 46. Qxf7+ { with a perpetual.}) 46. Rb2 Rxg3+ 47. fxg3 Qf1+ 48. Rg2 Rc2 $19) 45. Rxd4 Nxg3 46. fxg3 (46. Rxf4 Nxh5 {and Black is a full rook up, with the Nc6 next to fall.}) 46... Qf1+ 47. Kh2 Rxc6 48. Qxg5 Rc2+ 49. Rd2 Rxd2+ 50. Qxd2 Rc1 0-1

01 February 2019

Exchange sacrifices (intentional and unintentional)

Unfortunately most of my exchange sacrifices to date have been unintentional ones.  In other words, my opponent is able to win the exchange (a rook for a bishop or knight) because of an oversight on my part, but then I fight on with some positional compensation.  In some cases I can even win (as in Annotated Game #161) by focusing on maximizing the effectiveness of my minor pieces and playing aggressively to target my opponent's weaknesses.  Of course, it's even better to focus on doing that before you're down material.

Deliberate positional exchange sacrifices are a characteristic of master-level games, where the compensation obtained is intentional, with long-term positional and dynamic benefits.  (If it's an exchange sacrifice that leads by force to a mate or material gain, then it's not a "positional" sacrifice and should be thought of more as a combination.)  Although there is always a certain element of guesswork to any sacrifice without forcing winning variations, it's an indication of mastery to be able to identify concrete gains on the board, as well to have an intuitive feel for when an exchange sacrifice is a good (perhaps best) option.  I think pawn sacrifices are a related concept, and I have had a similar experience with them in that regard, although recently I've started to deliberately incorporate sacrificial ideas with pawns into my thinking.

Perhaps the clearest definition and explanation (with well-chosen illustrative examples) that I've seen is "Positional Exchange Sacrifices" by IM David Brodsky over at chess^summit.  This is a topic that gets referred to a lot, but not many people take the time to address it in depth, so it's well worth checking out.

27 January 2019

Training quote of the day #21

The most intelligent inspection of any number of fine paintings will not make the observer a painter, nor will listening to a number of operas make the hearer a musician, but good judges of music and painting may be so formed.  Chess differs from these.  The intelligent perusal of fine games cannot fail to make the reader a better player and a better judge of the play of others.
-- Emanuel Lasker, World Champion 1894-1921
(Cited in The Art of Planning in Chess: Move by Move by GM Neil McDonald)