05 December 2019

Commentary: 2018 US Championship, Round 1 (Onischuk - Akobian)

As part of my opening and general chess studies, I save professional/master-level games that I run across with direct relevance to my opening repertoire. Even if they aren't in exactly the same variations that I may use, the ideas and high-level play in these games repay the time invested in analyzing and studying them. It's been a while since I formally did a commentary game, but I expect to continue mixing them in with my own analyzed games. Both PGN annotated game collections are kept up-to-date and available for download via the sidebar links.

This next commentary game features a Dutch Stonewall from round 1 of the 2018 US Championship, between veteran GMs Alexander Onischuk and Varuzhan Akobian. Their play highlights a number of useful themes in the Stonewall, middlegame and endgame, including:
  • The idea of dissolving the Stonewall center and its consequences, especially the need for active central play.
  • Black's positional exchange sacrifice, for which he gets the center and a strong advanced passed pawn as compensation.
  • The strength of that central advanced passed pawn, which eventually decides the game
  • Akobian's practical decisions to simplify play to a less advantageous position, but one that is more easily played, rather than go in for additional complications.
It's an entertaining and instructive game, which among other things shows how the Stonewall can in fact lead to varied, active positions rather than stereotyped closed ones.

[Event "US-ch Men 2018"] [Site "Saint Louis"] [Date "2018.04.18"] [Round "1"] [White "Onischuk, Alexander"] [Black "Akobian, Varuzhan"] [Result "0-1"] [ECO "A90"] [WhiteElo "2672"] [BlackElo "2647"] [Annotator "ChessAdmin/Komodo 11.2"] [PlyCount "50"] [EventDate "2018.??.??"] 1. d4 e6 2. c4 f5 3. Nc3 Nf6 4. g3 d5 5. Bg2 c6 6. Nh3 {an interesting side variation in the Stonewall. White normally looks to dominate and place a minor piece on f4, while happening to restrain ...g5 in the process.} Bd6 {this is the standard Modern Stonewall placement of the bishop. Black must be alert to not playing into White's plans for the Nh3 however, for example by exchanging bishops on f4.} 7. O-O O-O 8. Qc2 dxc4 {transforming the center and initiating complications.} (8... Na6 $5 {scores best in the database, although only based off three games, all of which were in the 1990s. It is also Komodo's preference. In all cases, it was followed by ...dxc4. The text move appears to be the modern choice, dispensing with the knight development, although the last occurrence was played some four years before this game.}) 9. e4 {White needs to play actively in response and strikes back in the center, now that the d-pawn no longer influences e4. The immediate threat is e4-e5.} e5 {blocks White's forking threat and challenges for the center.} 10. exf5 exd4 ( 10... Na6 {is the engine choice, getting another piece developed and eyeing the b4 square.} 11. dxe5 Bxe5 12. Qe2 Qc7 13. Bf4 Bxf4 14. Qxc4+ Kh8 15. Nxf4 Bxf5 $14) 11. Ne2 c5 $146 {choosing to protect the d-pawn over the c-pawn.} ( 11... d3 $2 12. Qxc4+ $16) (11... b5 {was previously played.} 12. Nxd4 Qb6 13. Ne6 Bxe6 14. fxe6 Na6 15. Ng5 Rae8 16. Be4 Nxe4 17. Qxe4 g6 18. Nf7 Nc7 19. Nxd6 Rxe6 20. Be3 c5 21. Nxc4 Rxe4 22. Nxb6 axb6 23. Rfd1 b4 24. Rd7 Rf7 25. Rad1 Nb5 26. Rd8+ Kg7 27. Rb8 Re6 28. Rdd8 Nd4 29. h4 Nf5 30. Bg5 Nh6 31. Rd2 Ng4 32. Bd8 Ne5 33. Re2 Nf3+ 34. Kf1 Nh2+ 35. Ke1 Nf3+ 36. Kf1 Rd6 37. Bxb6 Rd1+ 38. Kg2 Rg1+ 39. Kh3 Rh1+ 40. Kg2 Rg1+ 41. Kh3 Rc1 42. Kg2 c4 43. Re3 Rg1+ 44. Kh3 Rh1+ 45. Kg2 Rg1+ 46. Kh3 Rh1+ 47. Kg2 Rh2+ 48. Kf1 Rh1+ 49. Kg2 Rh2+ 50. Kf1 Rh1+ {1/2-1/2 (50) De Jong,J (2424)-Ulybin,M (2538) Alghero 2011}) 12. Qxc4+ Kh8 13. Ng5 $6 {White misses the chance to immediately undermine Black's center.} (13. b4 $5) 13... Nc6 $11 {defending against the b-pawn advance.} 14. Bf4 {although there is no longer a Nh3, the Ne2 plays a similar role in supporting the bishop on f4. White does not attempt to protect the f5 pawn, which would be too awkward.} (14. Nf7+ {seems like a good move, winning the exchange, but is passed up by Onischuk. None of the engines like it either, showing equality at best for White.} Rxf7 15. Qxf7 Ne5 16. Qb3 Rb8 {and Black has full compensation for the exchange with the protected passed d-pawn, 4-2 mobile queenside pawn majority, and active piece placement. White's doubled f-pawn is also a weakness.}) 14... Bxf5 15. Nf7+ {now White goes for the exchange, with similar results to the above variation. There is not much of a choice, however, since Black otherwise is just a pawn up.} Rxf7 16. Qxf7 Rb8 ( 16... d3 $5 {is recommended by both Komodo and Stockfish, showing full equality. Perhaps Akobian did not want to enter the complications afterwards; the text move simplifies the position and is more predictable to play. The idea is put into practice shortly, in any case.}) (16... Ne5 $2 {as in the above variation no longer works, as there is no Bc8 now and the b-pawn is hanging.}) 17. Bxc6 bxc6 18. Rfe1 d3 (18... Rxb2 $2 {is avoided by Akobian, who no doubt spotted the response by White to sacrifice on d4 and open up the e-file for the Re1. This type of response is likely to be missed by Class players, who would focus on grabbing the pawn and assume that the d-pawn is still well-protected, without further evaluation.} 19. Nxd4 $1 {the point is that Black is forced to deal with the knight, which is attacking the Bf5 and c6, while White also creates threats involving the e-file.} cxd4 20. Bxd6 $18 { this is White's ultimate idea, which works due to Black's back-rank problem.} Bg6 (20... Qxd6 $2 21. Re8+) 21. Qe7 Qxe7 22. Rxe7 d3 23. Be5 Rb5 24. Rd1 $18) 19. Bxd6 $2 {without the e-file open, this idea no longer works for White.} ( 19. Rad1 {was necessary.}) 19... Qxd6 $15 20. Nc3 d2 21. Re7 {Black is vulnerable on the 7th rank here, rather than the 8th rank, so the position is defendable.} Rg8 22. Rxa7 $6 {Onischuk evidently felt that he had time to snatch the pawn, perhaps with the goal of advancing the a-pawn. However, this gives an extra tempo to Black, whose own passed pawn is much farther along on d2.} (22. Rd1) 22... Bg4 (22... Qd3 {is the engine recommendation, powerfully centralizing the queen. This does multiple things, including allowing the advance of the c5 pawn, threatening to penetrate via c2, and forcing White to worry about his airy king position.}) 23. Qe7 (23. Re7 $15) 23... Qxe7 { as before, Akobian goes for a simpler position with less of an objective advantage. This is a common practical decision, especially taking into account things like fatigue and time management.} (23... Qb8 {is the engine recommendation. For example, if} 24. Rb7 Qc8 25. Rc7 Qf5 26. Rxc6 Bf3 $19) 24. Rxe7 $15 Nd5 {the only move for Black. Now the pawn threatens to queen, since Black is in a position to remove the Nc3 and White's Re7 cannot get to the d-file to defend.} 25. Re2 $2 (25. f3 {is the only saving move for White.} Bxf3 {deflecting the bishop from covering d7.} 26. Rd7) (25. Nxd5 cxd5 $19 {and White loses material after an eventual d1(Q).}) 25... d1=Q+ $1 0-1

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