In the first game of the WCC 2012 between Anand and Gelfand, which was drawn, Gelfand had a passed pawn on a6. Could he not have exchanged the major pieces and then tried to win with it?
Why was the passer ignored and the draw accepted?
[Title "Viswanathan Anand-Boris Gelfand,Anand-Gelfand World Championship Match, Moscpw Russia, 5/11/2012"]
1.d4 Nf6 2.c4 g6 3.Nc3 d5 4.cxd5 Nxd5 5.e4 Nxc3 6.bxc3 Bg7 7.Nf3 c5 8.Bb5+ Nc6 9.d5 Qa5 10.Rb1 a6 11.Bxc6+ bxc6 12.O-O Qxa2 13.Rb2 Qa5 14.d6 Ra7 15.Bg5 exd6 16.Qxd6 Rd7 17.Qxc6 Qc7 18.Qxc7 Rxc7 19.Bf4 Rb7 20.Rc2 O-O 21.Bd6 Re8 22.Nd2 f5 23.f3 fxe4 24.Nxe4 Bf5