TCEC Season 17 Playoff for Div P Game 1: Ethereal-ChessFighter
|Game||Season 17, Playoff for Division P, Game 1|
|Links|| TCEC archive|
|Position after 13. Qd2|
1. d4 Nf6 2. c4 c5 3. d5 b5 4. Nf3 g6 5. cxb5 a6 6. b6 d6 7. Nc3 Bg7 8. e4 Nbd7
Book exit into Benko Gambit declined. By the Lichess masters database, this position is fairly double edged. The next move by white gives roughly equal statistics for all three results, although 9. a4 would have been somewhat favorable for white.
9. Be2 a5 10. O-O O-O 11. a4 Nxb6 12. Bf4 Ne8 13. Qd2 (diagram) Nc7
Perhaps black should have played 13... Bg4 right away, rather than on the next move. The problem now is that this gives white time to play Bh6 to exchange the fianchetto bishop on g7. With the more immediate approach, this would not have been the case: 13... Bg4 14. Bh6?! Bxf3 15. Bxf3 Nc4 16. Qc1 Bxh6 17. Qxh6 and black gets the pawn on b2 as compensation for the exchanged bishops.
|Position after 25. f5|
14. Bh6 Bg4(N) 15. Bxg7 Kxg7 16. h3 Bxf3 17. Bxf3 Nc4 18. Qe1
This is an important point in the game to consider long-term plans for black. Instead of 18... Ne5, now was the time to start challenging white's center control with moves such as 18... e6 or 18... e5. Instead, black moves the knight to the center where it becomes subject to give up a tempo after f4.
18... Ne5 19. Be2 c4 20. Qd2 Rb8 21. Kh2 Kg8
The last two king moves may seem mysterious at first. However, they both serve a purpose in preemptively avoiding tempo-gaining checks. The white king sidesteps the check with Qb6 in many lines after opening the diagonal with f4 and the knight on c7 moved away, and these moves were indeed played in the game. On the other hand, the black king sidesteps the check with Qc3. To illustrate the latter, consider 21... Rb7?! 22. f4 Nd3 23. Nb5 Nxb5 24. axb5 and the threat of 25. Qc3+ will be quite annoying to deal with.
White now begins to exploit the strong center, and pushes the f-pawn with tempo.
22. f4 Nd3 23. Rab1 Rb3 24. Bxd3 cxd3 25. f5 (diagram)
Now the problem of leaving white's center control unchallenged becomes concrete. Black cannot realistically take 25... gxf5 and hope to survive with an open king and defenders nowhere near the action. And letting white to take, as happens in the game, has its own drawbacks.
|Position after 31. Nd4|
25... Ne8 26. fxg6 hxg6
Taking back with the f-pawn would have been worse: 26... fxg6? 27. Rxf8+ Kxf8 28. Nb5. The threat is now for the white knight to enter either the c6 or the e6 square with a tempo on the rook with Nd4. To prevent that idea, black would have to play a move such as 28... e5 and open the king even further.
27. Rf4 Qb6
White was threatening mate with a simple idea of Rh4 and Qh6. The queen on b6 stops that idea for now, as it would be just in time to reach g7 via d4. Black will now further have to spend tempi to get the rook on the h-file for a bit more permanent defense against the mating idea. But this puts the king back to the vulnerable long diagonal.
28. Nb5 Kg7 29. Rc1 Rh8 30. Rc6 Qb8 31. Nd4 (diagram)
White is seemingly bold to allow black to take the b2 pawn with a tempo, but everything works out tactically. This begins a strong attack on black's position, and black seems to be always just a single tempo short of stabilizing.
White could have also played safer with a variation such as 31. Qf2 Nf6 32. e5 dxe5 33. Rfxf6 e4+ 34. Rf4 winning a piece. In this line black gets some compensation for the piece in form of connected passers, but it would not be nearly enough.
|Position after 45. Rxe7+|
31... Rxb2 32. Qc3
The threat is now a double check with forced mate. To illustrate: 32... d2?? 33. Nf5+ Kg8 34. Nxe7+ Kf8 35. Nxg6+ Kg8 36. Qxh8#. Black has only one viable move to prevent the threat, but it gives the white knight a strong square on e6.
32... f6 33. Rc8
A tricky back rank problem for black is posed. Black would need multiple tempi to free up the knight. Currently, the knight can only move to c7, but white already attacks that square twice.
33... Qb4 34. Qxd3
White avoids the queen trade on b4, which would have essentially allowed black to untangle and claim equality. White is now threatening to open the center and attack the vulnerable g6 square. If black does nothing, the simple idea of Rg4 and e5 will be a forced mate.
Black stops the threat, as the queen can now take on e5 with a check if the e-pawn is pushed. This also creates an answer for 35. Rg4, as 35... Rb1 would create enough counterplay to force the draw.
By playing 34... Qd2, black could have also forced the queen trade by threatening Qxg2#. But in the end, white would have been just in time to exploit black's back rank issues. The black rook ending in d2 rather than in b4 after the queen trade would have made all the difference. Example line: 34... Qd2 35. Qxd2 Rxd2 36. Ne6+ Kf7 37. Ra8 Rc2 38. Nd8+ Kg7 39. Ra7 Kf8 40. Rf3. Now white would be bringing the second rook to the queenside and black simply does not have enough space to defend the e7 pawn. 40... Rc8 41. Ne6+ Kf7 42. Rb3 f5 43. exf5 gxf5 44. Rbb7 Kg6 45. Rxe7.
35. Rf1 Qh4 36. Ne6+ Kf7 37. Ra8 g5
Black goes for counterplay, but white is again one crucial tempo faster with the attack.
38. Nd8+ Kf8 39. Kg1 Ra2 40. Ne6+
White would not have had the time to grab the pawn: 40. Rxa5?? g4 41. Ne6+ Kf7 42. Ra7 Rg8 43. Qb3 gxh3. White would now have to take the draw with either 44. Rxe7+ aiming for perpetual checks, or 44. Nd8+ Kf8 45. Ne6+ Kf7 46. Nd8+ repeating immediately. A losing mistake would have been to take the rook: 44. Qxa2?? Rxg2+ 45. Qxg2 hxg2.
40... Kf7 41. Ra7 g4 42. Qb3
The main point of bringing the queen to the b-file is to enable the Rxe7+ sacrifice with the queen following up with a check on the 7th rank.
42... Rg8 43. g3
White could have also taken the rook with 43. Qxa2 gxh3 44. Qb3 Rxg2+ 45. Kh1 winning with a forced mate in less than 30 moves. But pushing the g-pawn was simpler.
43... Rb2 44. Qe3
As before, taking the rook with 44. Qxb2 would also have been just fine for white with a decisively winning position, but white considered that keeping the Rxe7+ threat alive was even more decisive.
44... Qh8 45. Rxe7+ (diagram) Kxe7
Black could not have ran away with the king: 45... Kg6 46. Qf4 Qh5 47. Rxe8 removing the defender to f6 and black collapsing under the Qxf6 threat.
|Position after 59. Qf5#|
46. Qa7+ Nc7
Black has to give up the knight to make the e8 square available for the king.
47. Qxc7+ Ke8 48. Rf4 Rb1+ 49. Kf2 Rb2+ 50. Ke1 Rb1+ 51. Ke2
White decides to avoid putting the king on the c1-h6 diagonal with 51. Kd2. It would have allowed black to pin the rook on f4 with Qh6. However, this would not have changed anything, and either way, the position is a forced mate after 13 more moves.
51... Rb2+ 52. Kd1 Rb1+ 53. Kc2 Rb3
Inconsequential inaccuracy, giving in to the mate sooner. The most resilient defense was 53... Qh6.
54. Qd8+ Kf7 55. Qd7+ Kg6 56. Rxg4+ Kh6 57. Rh4+ Kg6 58. Nf4+ Kg5 59. Qf5# 1-0 (diagram)
White wins by mate.