1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. b1c3  3... f8b4  4. d1c2  4... e8g8  5. e2e4  5... d7d5  6. e4e5  6... f6e4  7. f1d3  7... c7c5  8. g1f3 An extremely sharp Nimzo-Indian line, the favorable choice of  Mamedyarov. 8... c5d4  9. f3d4  9... b8d7  10. c1f4  10... d8h4  11. g2g3  11... h4h5  12. h2h4  Vallejo's choice. The Spanish GM won a couple of games with this pawn  sacrifice. 12... d7e5  13. d3e2  13... e5g4  14. e2g4  14... h5g4 All of this is very forcing, and  both players definitely knew what they were doing. 15. f2f3  15... g4h5  16. g3g4  16... h5g6  17. f3e4  17... e6e5  18. e1c1 White returns the piece at once. 18... b4c3  19. d4f5  19... c8f5  20. g4f5  20... g6a6  21. c2c3  21... d5d4  22. c3b3 A novelty at move 22! 22... e5f4  23. d1d4  23... a8d8 An important move! With the swap of a rook  pair, Esipenko weakens the white kingside. 24. b3d3 Xiong parts with  an important pawn in exchange for control over the vital open file. 24... d8d4  25. d3d4  25... f8c8 In order to weaken the second rank. 26. b2b3  26... a6a2 Best again. 27. h1d1 Xiong also plays for a win. Despite the limited material on  the board, the energy in the remaining major pieces and the insecure  position of the kings leave both sides a huge amount of tactical  possibilities. 27... g7g6  28. f5f6 Insisting on the back-rank checkmate. 28... h7h5 So  far Esipenko has played flawlessly. But here and on the next move he  missed an important resource. 29. d1d3  29... a2g2 As strange as it sounds, this is a huge mistake. 30. d4d7  30... c8f8 Now that the black rook is out of the game, Xiong gets enough time to build more threats. 31. d7e7 Threatening to capture the rook. 31... g2g1  32. c1c2  32... g1b6 The only way to cover the d8-square. 33. d3d6 White can always force a draw if he wants as the black queen  cannot abandon the d8-square. 33... b6a5  34. d6d5  34... a5b6  35. d5d6 Xiong  first demonstrates this. 35... b6a5  36. d6d5 Then tries another  attacking idea. 36... a5b6  37. d5g5 Now the g6-pawn is a target. 37... b6f2 And  Esipenko does not find anything else but to look for perpetual. Alas, the  lonely queen is not capable of the task. 38. c2b1  38... f2e1  39. b1a2  39... e1d2 