The Extra

Alexandra Konstantinovna Kosteniuk – Irina Borisivna Krush

2nd Online Chess Olympiad Playoff; Russia – United States; Final match game 2; time control: 15 minutes plus 5 seconds per move; chess.com, September 15, 2021

Sicilian Defence B66

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 Nc6 6. Bg5 e6 7. Qd2 Be7 8. 0-0-0 a6 9. Nxc6. From a theoretical standpoint this should be an objectionable move as it strengthens Black’s centre, but computers and algorithms are not so dogmatic. 9. ... bxc6 10. Bxf6. The strategic alternative 10. Bf4 d5 11. Qe3 0-0 12. Be2 a5 13. Qg3 Ba6 14. Bf3 Nd7 15. h4 turned out not to be adequate for achieving theoretical acceptance: 15. ... Bf6 16. e5 Be7 17. Bh6 g6 18. Bxf8 Bxf8 19. h5 Bg7 20. hxg6 hxg6 21. Be2 Bxe2 22. Nxe2 Nxe5 23. c3 a4 24. a3 Nc4 25. Rh4 Qb6 26. Rxc4 dxc4 27. Qf4 Rb8 28. Rd2 Bf8 29. Nd4 Rb7 30. Qe4 Rd7 31. Re2 c5 32. Nc2 Qd6 33. Ne3 Bh6 34. Qa8+ Rd8 35. Qxa4 Qh2 36. Kb1 Qg1+ 37. Ka2 Bxe3 38. fxe3 Qf1 39. Qc2 Rd1 40. b3 Rc1 0 : 1 Lagno – 侯逸凡 (Hóu Yìfán), 2nd SportAccord World Mind Games, Women’s Rapid Tournament, 北京 (Běijīng) 2012. 10. ... gxf6 11. Bc4 0-0 12. Rhe1TN (12. h4 Kh8 13. g4 d5 14. Bb3 Bb7 15. Rhe1 Qc7 16. Kb1 Rad8 17. exd5 cxd5 18. f4 Qa5 19. Qd3 Rg8 20. g5 d4 21. Ne2 f5 22. Nxd4 Bc5 23. Qe3 Be4 24. Re2 Qb6 25. Red2 Bb4 26. Re2 Bc5 27. Red2 Bb4 28. Re2 Bc5 29. Red2 Bb4 30. Re2 Bc5 ½ : ½ Vocaturo – Greenfeld, 35th European Chess Club Cup, Ulcinj 2019) 12. ... Kh8 13. Re3 Rg8 14. f4 d5! 15. Qe2! Bd6

16. e5 fxe5 17. fxe5 Bc5. 17. ... Bf8! 18. Kb1 Qe7 19. Bd3 Rg7 was a sound defence, probably preferable to the text. 18. Rh3 Qg5+. Her best seems to be 18. ... f5!? 19. exf6 Qxf6 20. Rf1 Qg5+ 22. Kb1 e5! offering a Pawn to give new horizons to her pair of Bishops. 19. Kb1 dxc4? And finally Krush swallows the bait — by now there was hardly anything better than 19. ... Qxg2 20. Qh5 Qg6 21. Qh4→ and White’s attack continues.

The refutation is as spectacular as it is pretty forced: 20. Ne4! Qxe5. If 20. ... Qxg2 then 21. Rxh7+!! Kxh7 22. Nf6+ Kh8 (idem to say 22. ... Kh6) 23. Qh5+ Kg7 24. Qh7+ Kf8 25. Qh6+ Ke7 (25. ... Qg7 26. Rd8+ Ke7 27. Rxg8! Δ 27. ... Qxh6 28. Re8#) 26. Nxg8+ Ke8 (26. ... Qxg8 27. Qf6+ Ke8 28. Rd8#) 27. Nf6+ Ke7 28. Qh8 followed by mate in two. 21. Rh5 f5. 21. ... Qg7 22. Rg5+− avoids instant mate but at cost of surrender of any illusions.

22. Ng5! Qc7. Of course the Queen is taboo due to 23. Rxh7#, whilst 22. ... Qg7 would be equally followed by 23. Qe5! forcing mate in two moves. 23. Qe5+! Rg7 24. Rd8+! Qxd8 25. Rxh7+ Kg8 26. Qxg7# 1 : 0.