1.d4 Nf6 2.c4 e6 3.Nf3 d5 4.Nc3 c6 5.e3 Nbd7 6.Qc2 Bd6 7.Bd3 0-0 8.0-0 dxc4 9.Bxc4 b5 10.Be2 Bb7 11.Rd1 Qc7 12.Bd2 e5 13.Rac1 a6 14.b4 Rfe8 15.Bd3 Bxb4 16.Ng5 h6N A poor novelty (whether prepared or not), but it leads to sharp play where he can at least hope for a tactical chance. [16...Nf8 17.Nxb5 (Not bad, but not necessarily best.) 17...axb5 18.Bxb4 exd4 19.exd4 Qf4 has happened in several games, and while Black's position is certainly acceptable White is in no danger at all. So Karjakin tries to keep things as sharp as possible, needing a win to keep the match alive.]
17.Nxb5 axb5 18.Bh7+ Kf8 19.Bxb4+ c5 20.dxc5 Bc6 21.Be4 [21.Nxf7 Nxh7 22.Nd6 e4 23.Nxe8 Rxe8 isn't exactly bad for White, but it gives Karjakin the sort of promising imbalance he can use to make a real fight out of it.]
21...Nb8 [21...hxg5 22.Bxc6 Qxc6 23.Rd6 Qc7 24.c6+- ]
22.Nh7+ Nxh7 23.Bxh7 All basically forced since move 16. Now too Black has no choice, as normal moves leave him a pawn down with no compensation or winning chances.
23...g6 24.Rd6 Re7 25.h4 h5 This makes the sac even better for White, but what else? Black's position is completely lost anyway, and if he allows White's bishop to get out he's dead and down material too.
26.Bxg6 fxg6 27.Qxg6 Rxa2 28.Rcd1 Rf7 29.Qh6+ Rg7 30.Qf6+ Kg8 31.Rd8+ Kh7 32.Qf5+ Rg6 33.Qxh5+ Rh6 34.Qf5+ A massacre, but it's not really Black's play that's to blame so much as the competitive situation. [34.Qf5+ Kg7 35.Qf8+ Kg6 (35...Kh7 36.Qg8# ) 36.R1d6+ forces mate.] 1-0