Grandmaster Blunder

The trick that I used in the last post (Finding the Critical Move where the first link leads to the full game) worked. On reaching the diagrammed position, Pachman wrote, 'The first crisis in the game'. The main definition that Answers.com gives the word crisis is 'A crucial or decisive point or situation; a turning point.' The term 'crisis point' is better than 'the position of the critical move', and is used frequently by annotators.

Lasker played 23.Bxg6, which appears to be tactically correct. After ...fxg6, White has Qb3+, forking the King and Bishop. When the Queen captures the Bishop on b7, the Knight on a6 is trapped. Unfortunately for Lasker, his 23rd move was a blunder and deserves a '?'.

World Championship Match (g.10)
Berlin 1910
Schlechter, Carl

Lasker, Emanuel
(After 22...Qd5-h5)
[FEN "r4rk1/pb2ppb1/n1p3p1/7q/N2P4/P2BP3/2QB1P1P/2R1K1R1 w - - 0 23"]

After the intermediate moves, 23...Qxh2 24.Rf1, the game continued as calculated: 24...fxg6 25.Qb3+. Here Black played the surprising 25...Rf7 26.Qxb7 Raf8. All three annotators gave a '!' to Black's 26th move, which initiates an attack on the King. Now White was in trouble.