Chiron and Achilles

Ekaterina Aleksandrovna Lagno – Mariya Olehivna Muzychuk
2nd Cairns Cup; Saint Louis, February 9, 2020
Russian Defence C42

1. e4 e5 2. Nf3 Nf6. It’s the third time in a row that the Russian Defence has appeared on Muzychuk’s board! 3. Nxe5 d6 4. Nf3 Nxe4 5. d4 d5 6. Bd3 Bd6 7. 0-0 0-0 8. c4 c6 9. Re1 Bf5 10. Qb3 Nd7!? Apparently a novelty — but don’t call it a novelty! The most usual is 10. ... Na6 (indirectly defending the b-Pawn as 11. Qxb7 is met by 11. ... Nb4) 11. cxd5 cxd5 with tons of theory. 11. cxd5 Ndc5. That’s the (consistent) corollary of Muzychuk’s previous nuance. Now White must sacrifice Queen and Pawn for two Knights and a Bishop — no doubt a satisfying compensation. 12. dxc5 Nxc5 13. Bxf5 Nxb3 14. axb3 cxd5 15. Nc3 Qb6 16. Be3 Qxb3. All this already occurred in a game from one of the engines testing matches organised by the Swedish Chess Computer Association (SSDF), which continued: 17. Rec1 Rfe8 18. Bc2 Qxb2 19. Ra2 Qb4 20. Ra4 Qb2 21. Ra2 Qb4 22. Ra4 Qb2 23. Ra2 ½ : ½ Deep Hiarcs – Chiron, Sundsvall 2016, match game 2. So White’s next may actually be the first new move of the game! 17. Nd4!? Qc4 18. Ra4 Qc7 19. g3 Qd8. After 19. ... Bc5 20. Bf4 Qd8 21. Rd1 the isolated d5-Pawn is probably doomed anyway. 20. Rd1 Re8 (20. ... Bc5? 21. Ne6!) 21. Nf3. White has no hurry to cash in the Pawn, as after 21. Nxd5 Re5! 22. Nc3 Qe8 Black’s defence would be notably easier. 21. ... Qf6 22. Rxd5 Be5. Muzychuk has to clutch at straws to defend her case. 23. Nxe5 Qxf5 24. Rf4 Qc2 25. Nxf7. From a material standpoint, after 25. Rd2 Qc1+ 26. Kg2 Rxe5 27. Rd8+ Rxd8 28. Bxc1 White, with Bishop and Knight against Rook and Pawn, should stand slightly better — but Lagno apparently hopes not to spend too much time sitting here. 25. ... Qxb2. Maybe Black ought first to play 25. ... Rxe3! 26. fxe3 Qxb2∞ in order to mobilise as soon as possible her Queenside united passed Pawns; an indicative variation is: 27. Rc5 Qc1+ 28. Kg2 a5 29. Ne4 Qb2+ 30. Rf2 Qb3 31. Rc7 a4 32. Nh6+ gxh6 33. Nf6+ Kf8 34. Nxh7+ Kg8 35. Nf6+ drawing by perpetual check.

26. Nh6+. Lagno is content with a draw by perpetual check. Naturally, she was still in time to enjoy the slight material edge of two pieces against Rook and Pawn with 26. Bd4 (Δ Rd5-g5) 26. ... Qc1+ 27. Kg2 Qxf4 28. gxf4 Kxf7 29. Nb5 — it felt safe and risk-free, yes. But that was not what she wanted. 26. ... gxh6 27. Rg4+ Kf7 28. Rf4+ Kg8 29. Rg4+ Kf7 30. Rf4+ Kg8 ½ : ½.

Despite the drawn result, the game between Lagno and Muzychuk presented a penetrating theoretical challenge to the justification of White’s positional Queen sacrifice. Photo: Lennart Ootes/Saint Louis Chess Club.