Outside, Inside

Bibisara Erkhanovna Assaubayeva – 侯逸凡 (Hóu Yìfán)

3rd Tech Mahindra Global Chess League; Round-Robin; Fyers American Gambits – SG Alpine Pipers; time control: 20 minutes plus 2 seconds per move after move 40; Mumbai, December 21, 2025

Sicilian Defence B67

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 Nc6 6. Bg5 Bd7 7. Qd2 a6 8. 0-0-0 e6 9. f3 Be7 10. Kb1 b5 11. Nxc6 Bxc6 12. Bxf6 Bxf6 13. Qxd6 Qxd6 14. Rxd6 Rc8 15. Rd1 Ke7 16. Bd3 Bxc3! 侯逸凡 (Hóu Yìfán) has her say on the theory of this opening line in which Black sacrifices a Pawn for dynamic counterplay.
17. bxc3 Bd7 18. Kb2 Rc5 19. a4 Rb8 20. axb5 Bxb5

21. Bxb5?? An enormous blunder, which loses by force. White should return the Pawn by 21. Kc1! Rxc3 22. Kd2 Rbc8 leaving Black with a very comfortable ending but no apparent way to win it.
21. ... Rcxb5+ 22. Kc1 Rb1+ 23. Kd2 Rd8+ 24. Ke2 Rdxd1 25. Rxd1 Rxd1 26. Kxd1

White is a Pawn up, but Black’s outside passed a-Pawn wins easily.
26. ... Kd6 27. Kd2 Kc5 28. Kd3 e5 29. h4. If 29. c4 then 29. ... Kb4 as in the game.
29. ... h5 30. g4 g6 31. g5 a5 32. c4 Kb4 33. c5 (33. c3+ Kc5−+)
33. ... Kxc5 34. Kc3 a4 35. Kb2 Kb4 0–1.

In her game against Assaubayeva, 侯逸凡 (Hóu Yìfán) showed in exemplary fashion what an outside passed Pawn can mean in an endgame. Photos: Aditya Sur Roy/ChessBase India.