garyz: The Karpov-Bellon game was very interesting and contained the stunning rook sacrifice by Karpov to get the draw. I studied this game with the help of my computer running the Stockfish chess engine and I believe Karpov could have won the endgame.
I. Karpov played 36.Kg2? and my software went from +339 to 0. A better move I believe is 36.Qd1! My software gives it +327 with the following possible lines. A 36....Qf5 37.Kg2 d5 38.Qh1 Qh5 39.Rc8 h3+ 40.Qxh3 Qxh3 41.Kxh3 dxc4 42.Rxc4 Rb2 43.Kg2 +452
B 36....Qf5 37.Kg2 Rb2 38.Qf3 hxg3 39.Kxg3 Rb8 +448
C 36....Qf5 37.Kg2 Rb8 38.Qf3 hxg3 39.Kxg3 +472
II. Another option for White one move earlier is: 35.Qa1! instead of Karpov's 35.Qxf1. 35.Qa1 Qh3 36.Qxf1 Qxf1+ 37.Kxf1 +315
Of course just about anything else by Black on 35. such as 35...Bxd3? 36.Qxd4 wins quickly although Black can try a Rook sac at 37...Rh1+ and trade queens to play the exchange down.
In both alternative lines for White, the move made by Karpov is made one move later with greater effect. I have only analyzed these positions for a few minutes since I haven't tried to use the chess engine for overnight analysis.