Interesting "exchange for bishop pair" position

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Nordlandia
Posts: 2821
Joined: Fri Sep 25, 2015 9:38 pm
Location: Sortland, Norway

Interesting "exchange for bishop pair" position

Post by Nordlandia »

14. Rxe6 interesting but dubious per engines.

Latest stockfish dev is capable of holding this as white against Ceres and Dragon. Haven't been able to test against Lc0 yet.

[d]r2q1rk1/1p2b1pp/2n1pn2/p7/2Pp4/P4NP1/1P1N1PBP/R1BQ2K1 w - - 0 15

[pgn][Event "Lozovatsky Memorial-A 2021"]
[Site "https://lichess.org/SJZTRmA6"]
[Date "2021.01.15"]
[Round "1.1"]
[White "Ponkratov, Pavel (2623)"]
[Black "Simantsev, Mikhail (2366)"]
[Result "1-0"]
[WhiteElo "?"]
[BlackElo "?"]
[Variant "Standard"]
[TimeControl "5400+30"]
[ECO "E00"]
[Opening "Catalan Opening"]
[Termination "Normal"]
[Annotator "lichess.org"]

1. d4 Nf6 2. c4 e6 3. g3 { E00 Catalan Opening } c5 4. Nf3?! { (0.63 → 0.00) Inaccuracy. d5 was best. } (4. d5 d6 5. Bg2 exd5 6. cxd5 g6 7. Nf3 Bg7 8. Nc3 O-O) 4... cxd4 5. Nxd4 d5 6. Bg2 e5 7. Nf3 d4 8. O-O Nc6 9. e3 Be7 10. exd4 exd4 11. a3 Be6 12. Nbd2 a5 13. Re1?! { (-0.13 → -0.69) Inaccuracy. Qb3 was best. } (13. Qb3 Qc7 14. Re1 O-O 15. Ng5 Bg4 16. Nde4 Nxe4 17. Bxe4 h6 18. h3 Bh5 19. Nf3 Bf6) 13... O-O 14. Rxe6?! { (-0.47 → -1.07) Inaccuracy. Qb3 was best. } (14. Qb3 Ra6) 14... fxe6 15. Ng5 Qd6 16. Qb3 Nd8 17. Ndf3? { (-0.98 → -2.16) Mistake. Qd3 was best. } (17. Qd3 Qb6) 17... a4?? { (-2.16 → -0.52) Blunder. h6 was best. } (17... h6 18. Nh3) 18. Qd3 e5?! { (-0.55 → 0.33) Inaccuracy. h6 was best. } (18... h6 19. Ne4) 19. Nh4? { (0.33 → -1.12) Mistake. Nxe5 was best. } (19. Nxe5 Qxe5 20. Bd5+ Kh8 21. Bf4 Qxg5 22. Bxg5 Nxd5 23. cxd5 Bxg5 24. Qxd4 Bf6 25. Qb4 Nf7) 19... e4?! { (-1.12 → -0.35) Inaccuracy. Nf7 was best. } (19... Nf7) 20. Nxe4 Nxe4 21. Qxe4 Ra5 22. Bd2?! { (0.00 → -0.51) Inaccuracy. Nf3 was best. } (22. Nf3 Raf5 23. Bf4 Rxf4 24. gxf4 Rxf4 25. Qc2 Qf6 26. Re1 Nc6 27. Qd1 h6 28. b4 axb3) 22... Re5 23. Qg4 Bxh4?! { (-0.79 → -0.09) Inaccuracy. Kh8 was best. } (23... Kh8 24. f4) 24. Bb4 Qe6?? { (0.00 → 1.92) Blunder. Qf6 was best. } (24... Qf6 25. Bxf8) 25. Qxh4?? { (1.92 → -0.08) Blunder. Bd5 was best. } (25. Bd5 Rxd5 26. Qxe6+ Nxe6 27. cxd5 Re8 28. dxe6 Be7 29. Bxe7 Rxe7 30. Rd1 Rxe6 31. Rxd4 Rb6) 25... Re8 26. f4 Rf5 27. Re1 Qd7 28. Be4 Nc6 29. g4 Rxe4 30. Rxe4 Rf7?! { (-0.02 → 0.67) Inaccuracy. Rf6 was best. } (30... Rf6 31. g5) 31. Bd2 d3?! { (0.46 → 1.31) Inaccuracy. Re7 was best. } (31... Re7) 32. h3? { (1.31 → 0.00) Mistake. Kf2 was best. } (32. Kf2) 32... Nd4 33. Qf2 Nb3 34. Qe3 h6?? { (0.00 → 2.33) Blunder. Nxd2 was best. } (34... Nxd2 35. Re8+ Rf8 36. Rxf8+ Kxf8 37. Qxd2 Qd4+ 38. Kg2 Qe4+ 39. Kf2 Kf7 40. c5 h6 41. Qe3) 35. Re8+ Kh7?? { (2.64 → 7.52) Blunder. Rf8 was best. } (35... Rf8 36. Re7 Qd4 37. Qxd4 Nxd4 38. Kf2 Nb3 39. Ke3 Nxd2 40. Kxd2 Rxf4 41. Rxb7 Rxc4 42. Kxd3) 36. Qe4+ g6 37. Bc3 Rg7 38. Bxg7 d2? { (8.36 → Mate in 4) Checkmate is now unavoidable. Qxg7 was best. } (38... Qxg7 39. Re7 d2 40. Rxg7+ Kxg7 41. Qxb7+ Kf8 42. Qd7 Kg8 43. Kf2 Nc5 44. Qe8+ Kg7 45. Ke2) 39. Rh8+ { Black resigns. } 1-0[/pgn]
User avatar
Nordlandia
Posts: 2821
Joined: Fri Sep 25, 2015 9:38 pm
Location: Sortland, Norway

Re: Interesting "exchange for bishop pair" position

Post by Nordlandia »

Stockfish fought bravely but unfortunately had to admit defeat in the end. It looked like a fortress for a while but Leela found a way to break in.

TC: 30m+45s | Game duration 2.5 hours.
Leela net: J94-130

[pgn][Event "i7-5960X 4.5GHz / 2x 2080 Supe"]
[Site "i7-5960X 4.5GHz / 2x 2080 Supe"]
[Date "2021.01.15"]
[Round "?"]
[White "stockfish_21011322_x64_bmi2"]
[Black "lc0-pro"]
[Result "0-1"]
[SetUp "1"]
[FEN "r2q1rk1/1p2b1pp/2n1pn2/p7/2Pp4/P4NP1/1P1N1PBP/R1BQ2K1 w - - 0 15"]
[PlyCount "131"]
[EventDate "2021.??.??"]

15. Ng5 Qd6 16. Bh3 Nd8 17. Nde4 Qc6 18. Qc2 Nxe4 19. Nxe4 Nf7 20. Bg2 Qd7 21.
c5 Ne5 22. Bf4 d3 23. Qd2 Rf5 24. b3 g5 25. Bxe5 Rxe5 26. Qc3 Qc7 27. Rd1 Bxc5
28. Rxd3 Rf8 29. Re3 Rc8 30. Nf6+ Kf7 31. Ng4 Rxe3 32. Qf6+ Ke8 33. Nxe3 Qe7
34. Qe5 Rd8 35. Bxb7 Bd4 36. Bc6+ Kf8 37. Qe4 Qf6 38. b4 axb4 39. axb4 Qe5 40.
Qxe5 Bxe5 41. Kf1 Bc7 42. Ke2 Rd4 43. b5 Bb6 44. Nd1 Rb4 45. Ke1 Rb3 46. Kd2
Ra3 47. Ke2 Ra2+ 48. Kf1 Ke7 49. Bf3 Ra3 50. Be2 Bd4 51. Ke1 Kd6 52. Kd2 h6 53.
Ke1 e5 54. Bh5 e4 55. Be8 Ke5 56. Bf7 Ra8 57. Bh5 Rb8 58. Be2 Bc5 59. Kf1 Bd4
60. Ke1 Bc5 61. Kf1 Rf8 62. Ke1 Ra8 63. Kf1 Bd4 64. Bg4 Ra5 65. Be2 Kf5 66. Ke1
Ra1 67. Bh5 Rb1 68. h3 Rxb5 69. Kf1 Ra5 70. Ke2 Bb6 71. Bf7 Bd4 72. Ke1 Ke5 73.
Bg6 Ra6 74. Be8 Bc5 75. Bf7 Kf5 76. Bh5 Bb6 77. Kf1 Ba7 78. Kg2 Ke5 79. Kf1 Kd4
80. Be8 0-1[/pgn]