1. d4 Nf6 2. c4 g6 3. Nf3 Bg7 4. g3 d5 Grischuk is not known for playing the Gruenfeld, but it makes sense when you consider the Gruenfeld master, Peter Svidler, is acting as one of his seconds.
5. cxd5 Nxd5 6. Bg2 Nb6 7. Nc3 Nc6 8. e3 O-O 9. O-O Re8 10. Re1 a5 11. Qe2 Bg4 An unusual subtlety, normally the bishop goes directly to e6, but for some reason Black wishes to provoke h3. Wang Yue used this idea successfully against Leitão in 2010.
12. h3 Be6 13. b3
Not the most common reply to Be6, the game now enters unknown waters.
13... a4 14. Rb1 axb3 15. axb3 Qc8 16. Kh2
16... Ra5 Grischuk targets the kingside in a powerful and threatening manner. Black's rook swing to the kingside seems to be strong; but Gelfand pays no heed to it!
17. Rd1 Gelfand simply develops, hoping to beat back Grischuk's attack with normal moves and banking on the strength of his center pawns.
17... Rh5 18. Nh4 Bf6 19. f4 19. Bf3 Rxh4 20. gxh4 Bxh3 and Black has compensation for the missing exchange; his pieces are better coordinated and White's king is somewhat exposed.
19... Rd8 20. Qf2
20... Bxh4? This exchange is premature. The bishop loses its influence on the a1-h8 diagonal which was preventing the d5 advance. Black doesn't get anything tangible in return, as the knight on h4 was somewhat misplaced. However, it is not so easy to come up with a good move. In a way, White has an easier time finding moves. He still hasn't finished development and wants to get his central pawns rolling. Although Black's pieces seem to be very active, they are also quite vulnerable.
20... Nd5 immediately was stronger. 21. Nxd5 Rdxd5! and the position is quite complex.
21. gxh4 Nd5 22. Nxd5 Rhxd5 22... Rdxd5? Or Bxd5 were now impossible because 23. e4 wins a lot of material. This wouldn't have been possible with the bishop still on f6.
White's development is almost finished, which means the pawns will start to roll. Grischuk must defend against this, but it is not clear how to do it.
23. Bxd5? Bxd5 gives Black a permanent grip on the light squares and leaves White in a planless position.
23... Rb5?! 23... Qd7 was maybe a better attempt, but after 24. e4?! (24. Rd2! playing it slow, with the idea of Rbd1. Black still has problems.)
24... Rxd4 25. Bxd4 Nxd4 it's complicated, but White is better.
24. Qe2 Rh5 25. e4 Bxb3 26. Rdc1
Black may have an extra pawn, but his position is almost lost. He has lost all coordination and White's bishops, supporting the strong pawn center, will steamroll through.
26... Na5 27. d5 b6 28. Be5 c5 29. dxc6 f6 30. Ba1 Rc5 31. Rxc5 bxc5 32. Qb5 Qc7? Losing quickly, but the position was probably already beyond saving.
32... Ba2 33. Rb2 Qc7 and f4 is under attack, which gives Black time to save his pieces. However after 34. e5 Be6 35. Qb6 Black is still lost.
33. Rxb3 Nxc6 33... Nxb3 34. Qxb3+ Kf8 35. e5 and Black has no useful moves.
34. e5 Nd4 35. Qc4+ Gelfand kept an amazingly cool head when faced with Grischuk's unorthodox but seemingly dangerous attack on the kingside. The Russian misplayed his attack by trading his important dark squared bishop, a mistake that Gelfand punished ruthlessly. Interestingly, this coup de grace was the only White victory in all of the classical time controls in this tournament!