Two Halves

Stockfish – Stoofvlees

Top Chess Engine Championship Season 20 — FRC3 Final League; tcec-chess.com, March 14, 2021

rqkbbnnr/pppppppp/8/8/8/8/PPPPPPPP/RQKBBNNR w HAha - 0 1

Position #697

1. d4 d5 2. c4 dxc4 3. Ne3 c5 4. dxc5 Nf6. Here the alternative was to maintain the symmetry with 4. ... Ne6 (5. Nf3 Nf6), but in any case the text, though not strictly symmetrical, is not too asymmetrical either. Black temporarily sacrifices a Pawn to keep development going. 5. Qc2 Ne6 6. Qxc4 Qe5 7. Bb4. Yet it is not too surprising that a machine wants to hold on to its material advantage. 7. ... a5 8. Ba3 Bc7 9. Nf3 Qh5. Also worth considering was 9. ... Qf4 followed by a-side castling (0-0-0) — whether before or after the exchange of Queens is irrelevant. 10. g4! Qh6

11. g5! Only thus. If, instead, 11. h4? then 11. ... Qf4! 12. Qxf4 Bxf4 13. Nd2 0-0-0! with powerful advantage. 11. ... Nxg5 12. Nf5 Qh3 13. Nxe7+ Kb8 14. c6! After 14. Nxg5 Qg2 Black wins back the Knight with good play for the Pawn. 14. ... Ra6. Not 14. ... b6?? because of 15. Nxg5 Qg2 16. Qb5! Qxh1 17. Bd6! winning immediately. 15. cxb7 Rb6 16. Nxg5 Qg2 17. Re1 Qxg5+ 18. e3

18. ... Bb5! Probably the only move. Black gives up a third Pawn in order to keep his chances of survival as high as possible. Incidentally, Black could not take on b7 either with the King or with the Rook on account of White’s Bishop going to f3. 19. Qxf7

19. ... Bd6? But Black eventually goes astray. 19. ... Rd8! was the consistent corollary of its previous move, since after 20. Bb3 (20. Bf3 should not worry Black too much after 20. ... Qh4) 20. ... Be2! 21. 0-0-0 Bxd1 22. Rxd1 Qb5!∞ it is anything but clear how White can make any progress. 20. Bxd6+ Rxd6 21. Bc2 Bd7? There’s something tremendously human about Black’s last error. ⌓ 21. ... Rd7! still gave some chances of putting up a defence. 22. h4 Qg2 23. Qc4 Re6 24. 0-0-0! A most powerful developing move! The rest is simply technique. 24. ... Qxb7 25. Rd3 Rb6 26. Red1 Re8 27. Nd5 Rc6 28. Qf4+ Ka8 29. Rb3 Nxd5 30. Rxb7 Nxf4 31. Rdxd7 Nd3+ 32. Kb1 Nc5 33. Ra7+ Kb8 34. Rxg7 Rd8 35. a3 Rd2 36. Rxa5 Rxf2 37. Rb5+ Ka8 38. Rg4 Rf1+ 39. Ka2 Rf7 40. Rc4 Rfc7 41. Bxh7 Rxh7 42. Rcxc5 Re6 43. Rc4 Ra6 44. Rcb4 Re7 45. h5 Rh7 46. e4 Rb7 47. Rxb7 Rxa3+ 48. Kb1 Ra1+ 49. Kc2 Rc1+ 50. Kd3 Rc3+ 51. Kd4 Rd3+ 52. Kc5 Rd5+ 53. Kb6 Rd6+ 54. Kb5 Rd1 55. Rb6 Rc1 56. Ra4# 1 : 0.