Originally posted by danilop
That's what you did from the very beginning of the game, not just in the ending. The decisive mistake was probably 42. bxc4, indeed, but your opponent already has a clear advantage in that position, thanks to your passive play early on. 33. dxc5, for example, gives him space, control of the center and allows the creation of a strong passed pawn.
Okay; I'll admit I was playing for the draw from move 1. I often do that when I am playing against better players (my opponent in that game was rated about 200 points above me when the game started). I guess I need to work on that, but I'm too tentative when playing better players.
Sometimes playing for the draw works, like in
Game 5623049
Game 5399552
Sometimes it doesn't, as in the game cited above and in
Game 5598938
Sometimes, however, sitting back and playing for a draw and waiting for a mistake by one's opponent can work. Take
Game 5598868 against the same opponent
1. d4 Ng8f6 2. Ng1f3 g6 3. c4 Bf8g7 4. Nb1c3 O-O 5. e4 d6 6. Bf1e2 Nb8d7 7. O-O c5 8. h3 cxd4 9. Nf3xd4 Nd7c5 10. Be2f3 Nc5d7 11. Bc1e3 Nd7e5 12. Bf3e2 Bc8d7 13. f4 Ne5c6 14. Be2f3 Nc6xd4 15. Be3xd4 Bd7c6 16. Rf1e1 Nf6d7 17. e5 dxe5 18. fxe5 Bc6xf3 19. Qd1xf3 Qd8c7 20. b3 Nd7xe5 21. Bd4xe5 Bg7xe5 22. Nc3d5 Qc7c5 23. Kg1h1 Be5xa1 24. Re1xa1 Ra8e8 25. Ra1e1 Qc5d6 26. Qf3c3 f6 27. Qc3f3 e5 28. Qf3e3 b6 29. Re1f1 Rf8f7 30. g4 f5 31. gxf5 Rf7xf5 32. Rf1xf5 gxf5 33. Qe3g5 Kg8h8 34. Qg5xf5 Qd6g6 35. Qf5xg6 hxg6 36. Kh1g2 Re8f8 37. a3 Kh8g7 38. b4 Rf8f7 39. c5 bxc5 40. bxc5 Rf7d7 41. Nd5b4 Rd7c7 42. c6 a5 43. Nb4d3 Kg7f6
I played 20. Nxe5, figuring he'd play 21. Qe3. I was then prepared to play 21. ... Nf3+ 22. gxf3 (not 22. Qxf3 Bxd4+ and white is in trouble) Qg3+ 23. Kh1 or Kf1 Qxh3 check and I have a perpetual check. I don't think he can play Ke2 because of ... Qg2+, in which case Qf2 loses the bishop and white is down 2 pawns and moving the King to the d file allows me to pin and probably win the bishop by moving a rook to d8. I haven't calculated all the variations, but I was pretty confident I'd have at least a draw.
In any case, he played what I think was a weaker move 21. Bxe5 and then followed it up by 22. Nd5 overlooking 22. ... Qc5+! winning the exchange and eventually the game.
As long as you're playing against a human being, sitting back and waiting for a mistake can be a good strategy.