context: 1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. b1c3  3... f8b4  4. d1c2  4... e8g8  5. e2e4 From time to time, players with White try to exploit the complicated variations that arise from this straightforward move. The problem is that the lines are already well studied, but Keymer certainly had everything very well prepared and the risk is small. 5... d7d5 Considered by theory as the main move to equalize. 6. e4e5  6... f6e4  7. a2a3 A much rarer move than 7.Bd3 and one that had been somewhat forgotten, having not been played at the highest level for some time. Keymer was probably counting on the surprise factor. 7... b4c3  8. b2c3  8... c7c5  9. f1d3  9... c5d4  10. c3d4  10... b8c6  11. g1e2  11... d8a5  12. e1f1  12... f7f6 The most accurate move. 13. d3e4  13... d5e4  14. e5f6  14... f8f6  15. c1e3  15... c8d7 One of many possible moves. 16. f1g1 The best move. White shouldn't be in a hurry to capture on e4. 16... a8f8 The first new move in the game. Of course it's very natural to double rooks on the f-file, but it's probably even better to maneuver the knight immediately. 17. h2h4 A thematic move that pops up in many lines, as the careful reader has already noticed. The idea is to give luft to the king and also prepare the rook lift with Rh3. White again should exercise patience before going after the e4-pawn. Black is ready to play with e6-e5 with good play. 17... c6e7 This is Black's only meaningful plan. 18. c2e4  18... e7f5  19. e3g5  19... f5d6  20. e4d3  20... f6f2 A risky move, quite in Wei's style. He's very confident in his calculations. 21. g5e7  21... d7c6  22. h1h2 Not allowing Black to start an attack. 22... a5f5  23. d3f5  23... f8f5  24. d4d5 A very interesting decision, posing problems for Black. 24... e6d5  25. e2g3  25... d6c4  26. e7c5  26... f2f4  27. g3f5  27... f4f5  28. c5a7 Black has some compensation, but it's White who will play for a win without any risk, a situation that is always unpleasant for the defender. 28... b7b6  29. h2h3 One of the very few inaccuracies by Keymer in this game. 29... f5f7  30. a7b8  30... d5d4 A bit premature, as the game continuation demonstrates. 31. a1c1 