aulero: Taimanov: "Every game with Botvinnik is an event for any player ..."
42.e4 was a sealed move and the players starting to analysing the game (together).
Botvinnik remarked: "A repetition of the past - I lost a similar ending thirty years ago in my match with Levenfish. Now I have mastered the way to play such endings."
Botvinnik: "Let us suppose that white has played 42.e4. Then there comes
42...a5 43.a4 e5! 44.Kf5 Kxh5 45.Kxe5 g4 46.Kf4 Kh4 47.e5 g3 48.e6 g2 49.e7 g1=Q 50.e8=Q Qf2+ 51.Ke5 Qe1+.
That is the way Levenfish won my queen."
Taimanov then opened the sealed enevelop, and wrote "and resigns" on his score sheet.
The king and pawns ending is the most nice I ever seen in a played game.
Botvinnik explained that the decisive white error was the transition of the K+R+P ending in the K+P ending:
31.Rxc1! (not 31.Rd4) Rxc1+ 32.Ke2 Tc2+ 33.Ke3 Rxa2 34.Rd4! and white should draw the ending.
Also 33.Rxe4 Rxa2 34.g4! followed by Kf1-g2 is better (according to Botvinnik).
After 36...Rg4!! forcing the pawn ending, white is lost: this move reveal deep calculation and considerable confidence as the decision is very committal.