TCEC Season 18 Top of the Top Bonus Game 53: Leela-Stoofvlees
|Game||Season 18, Top of the Top Bonus, Game 53|
|Links|| TCEC archive|
Work in progress
|Position after 13. Re1+|
End of book
1... e5 2. g3 Nf6 3. Bg2 c6 4. Nf3 e4 5. Nd4 Qb6 6. Nb3 a5 7. d3 a4 8. N3d2 d5 9. cxd5 exd3 10. O-O cxd5 11. exd3 Nc6 12. Nc3 Qa5 13. Re1+ (diagram)
|Position after 24... Qb6|
13... Be6 14. Bh3 Nd8(N)
White exercises the pin on the king, asserting some pressure against the king in the middle. Black intends to capture back with a knight.
In the only masters game in this position, black invited white to take a pawn: 14... Be7 15. Bxe6 fxe6 16. Rxe6 O-O. As compensation, black gets the open f-file for an attack. The game ended in a quick draw.
15. Nf3 Be7 16. Bxe6 Nxe6 17. a3
White prevents black from playing Bb4 and pushing a3 at an opportune moment.
17... O-O 18. Be3 Rfe8 19. Rc1 h6 20. Kg2 Bf8 21. h3 b5 22. Bd4 Nxd4 23. Rxe8 Nxe8 24. Nxd4 Qb6 (diagram) 25. Nce2
Grabbing the b5-pawn here was not advisable:
- 25. Ncxb5?! Bc5 26. Qg4 Nf6 27. Qh4 Ra5 28. Qf4 Rxb5 29. Nxb5 Qxb5 and black gets two knights for a rook.
- 25. Ndxb5?? d4 simply losing a piece.
|Position after 33... Qb3|
25... Bc5 26. Nf5 b4
The f2-pawn was not for taking: 26... Bxf2? 27. d4! interrupts the queen-bishop communication. Black can fight back for couple of moves, but the bishop is essentially lost: 27... Qe6 28. Qd3 Nf6 29. Nf4 Qd7 30. Rc6. Now white is threatening Nxh6+ gxh6 Rxf6, and taking the rook with 30... Qxc6 would lose to Ne7+ forking the queen. This line is a losing battle for black.
27. axb4 Bxb4 28. Rc2 Bf8 29. Qc1 Qb3 30. Qd2 Nd6
White is mounting some pressure against the black kingside. Attempting to relieve some pressure by offering a piece exchange makes sense.
31. Ned4 Qb7 32. Qf4 Nxf5 33. Nxf5 Qb3 (diagram)
A tempting move, intending to make white choose whether to give up a pawn or go passive with moves such as Rd2 or Qd2. However, allowing white to take the seventh rank was a mistake, and white is happy to give up a pawn for the opportunity to do so. A better move was 33... Ra7 protecting the f7-pawn and maintaining the rough equality.
|Position after 37. h4|
White takes the 7th rank with the exposure threat of Qxf7+.
Black allows Qxf7+, inviting the knight sacrifice on h6. The queen controls the h7 square, which prevents the sacrifice resulting in an immediate mate with Qxf7+ and Qxh7#. But allowing Qxf7+ was the final mistake, passing the point of no return.
The last drawing chance for black was sacrificing the d-pawn to unblock the queen's visibility to the critical f7 square: 34... d4 35. Qxd4. However, as Stoofvlees's evaluation for the following moves indicates, Stoofvlees did not consider the sacrifice winning for white.
35. Nxh6+ 35... gxh6
White is now winning.
Not accepting the piece sacrifice was also hopeless: 35... Kh7 36. Nxf7 Qe4+. Exchanging the queens here is the most resilient move: 37. Qxe4+ dxe4 38. Ng5+ Kg6 39. Nxe4. But still, two pawns up is an easy win for white.
36. Qxf7+ Kh8 37. h4 (diagram)
Now as the dust has settled a bit, it is time to analyse the position. The problem for black is that the bishop must guard the g7 square and the queen has to guard the h7 square. This restricts black's options severely. But if black was able to exchange the queens or rooks to defuse the attack, black would have good chances for winning.
White has two simple plans:
- Interrupt the black queen's visibility to h7 by pushing the f-pawn to f5. This would enable Qh7#.
- Win the black rook by forking the rook and king with the queen. The black king is open and the rook cannot leave the 8th rank protecting the bishop.
Black's options to avoid losing are the following:
- Keep the queen on the b1-h8 diagonal and prevent white from closing it
- Exchange pieces
- Perpetual checks
White's move 37. h4 was essential to prevent perpetual checks by black, or even worse, getting mated if the black rook is allowed to activate. Now the white king has an escape route.
|Position after 42... Qc2|
37... Rb8 38. Ra7
Prepares the forking threat, as the black rook no longer hides behind the white rook.
38... Qe4+ 39. f3
The only move that maintains the win for white, taking a key square away from the queen on the all-important b1-h7 diagonal. Namely, it prevents the queen coming back to e8 via e4 (or Qe2+) after the white king is forced to h5. If that was allowed, black would have been able to exchange queens with Qe8 x-raying the king.
39... Qe2+ 40. Kh3 Qf1+ 41. Kg4 Qc4+ 42. Kh5 Qc2 (diagram)
To illustrate the rationale behind 39. f3. If the pawn on f3 was on f4, instead, now black would play 42... Qe2+ 43. g4 Qe8 and white's attack is over.
The simplest and probably the fastest way to win here was to push the g4-pawn, threatening f4-f5 and liberating the white queen from guarding the f5-square to prevent Qf5# mate by black. Example line: 43... d4 44. Qf6+ Kg8 45. Qe6+ Kh8 46. Qe5+ Kg8 47. Qd5+ Kh8 48. Qxd4+ Kg8 49. Qd5+ Kh8 50. Qe5+ Kg8 51. Qxb8 winning the d-pawn and the rook. As white has a pawn on g4, there is no Qf5# for black.
|Position after 51... Qa2|
43. Rc7 Qd3 44. Qf6+ Kg8 45. Qf4 Kh8 46. Qf7 Qb1 47. g4 d4
Threatening now Rb5+. White uses the zigzag maneuver to get the queen to the fifth rank to prevent the threat.
Note that pushing the f-pawn to defuse Rb5+ threat does not work here: 48. f4 Qe4 and the only way white can prevent Qe8 is Qf6+/Qf7+ perpetual.
48. Qf6+ Kg8 49. Qe6+ Kh8 50. Qe5+
The white queen is now in the ideal position for the f5 push: black's defensive attempts Bg7, Rb5+ and Qe4 are all prevented.
Also winning was the earlier f-push but there was no reason to allow Bg7 to complicate the matters: 50. f4 Bg7 51. f5.
50... Kg8 51. f4
Now f5 cannot be stopped anymore, only delayed.
51... Qa2 (diagram)
Keeping the queen in the b1-h7 diagonal no longer works: 51... Qd3 52. Qe6+ Kh8 53. Qf6+ Kg8 54. f5. Therefore, black tries one last trick hoping white to push the f-pawn now.
|Position after 57. Qg7#|
But engines at this level do not fall for such tricks, and white simply renews the threat of Qh7#.
Pushing the f-pawn here was in fact losing: 52. f5?? Rd8 with black turning the tables. The key here is that the black queen is guarding the f7 square preventing the Qf7+ and Qh7# mate. Depending on what white does, black would now have the resources to defuse the attack:
- 53. Qf6 Rd6
- 53. Kg6 Rd6+ 54. f6 Qe6
- 53. Ra7 Rd6 54. Qa5 Qc4 (preventing 55. Qc7)
More resilient, but still hopeless: 52... Bg7 53. Qd7
53... Qd5+ 54. f5
White is now finally able to push the f-pawn to interrupt black queen's visibility to the h7-square. Black has only the final delaying moves left.
54... Be7 55. Rxe7 Qxf5+ 56. gxf5 Rb6 57. Qg7# 1-0. (diagram)
White wins by mate.
- David Navara vs Fabiano Caruana St. Louis Rapid & Blitz (2017), blitz round 5. https://www.chessgames.com/perl/chessgame?gid=1883820
- Ding Liren vs Fabiano Caruana PRO League Group Stage (2019) (rapid), chess.com, round 7. https://www.chessgames.com/perl/chessgame?gid=1961535
- Szczepanski, Zbigniew vs Johansson, Krister (2016). Correspondence? https://lichess.org/H7EcfsHx#28