In the 1954 World Championship Match, Smyslov led 6-5 after 11 games. Botvinnik had scored 1/2 out of 5 in the 5 games before the 12th game, and it seemed as if he was finished. However, it became what he would call his greatest achievment of the match.
It is a very modern game and perhaps one that the commentators underestimated. Botvinnik played consistently throughout it and the two players staged a battle of plans.
Oh, and I recently got the book Kasparov Against the World. I would recommend it to everyone on chess.com. And it's interesting many people have left chess.com, only to return under a new account (Rae1, Chess_Nut, The_Blakenator). Guess you can't take chess out of anyone.