Game No. 104 in the book (round 12): a Ruy Lopez won by Emanuel Lasker (Black) against Julius Perlis, annotated by Lasker.

1. 9…Be7 This appears to be better than the usual 9) .... B - Q B 4, as the square Q B 4 remains open for the Kt and the Q B P.
2. 10.a4 This move was feasible, before Black's Bishops had moved. But now it is a mistake, which disorganizes White's Queen's wing.
3. 10…b4 The correct reply. This would not do if Black were not ready yet for Castling, on account of P - R 5 and B - R 4.
4. 20…Qd5 So far Black has conducted the attack correctly and White has defended well. For in spite of the danger to expose his King, the latter was bound to advance his Pawns, as he did, for counter attack, in order to establish a pressure on his opponent's King's side. But here Black fails to find the right move. 20) .... P - Q 6 should have been played, to free the Bishop and render Q 5 accessible to the Knight. It is true that this move would give the square K 3 to White's Bishop, and the Pawn would be weak at Q 6, but the attack on the King would more than compensate for these disadvantages; e. g.: 20) .... P - Q 6; 21) Q - B 3, Kt - Q 5; 22) Q x P, Kt x B; 23) Q x Q ch, R x Q; 24) P x Kt, B x P and Black, with two Bishops on the open board, and several weak spots in his opponent's camp, would have a splendid game.
5. 28…f6 This looks much stronger than it really is. As a matter of fact, 28) .... R - Q 2 would have been better. Then if 29) Q R - K 1, R ( Q 2 ) - K 2. The Queen's Pawn cannot be captured on account of Kt - K 3, and P - B 3 would follow soon with great effect.
6. 30.e6 White is wrong in being afraid to capture the Pawn. After 30) P x P, Kt x P; 31) R - K 5 White would win the Q R P, and 30) .... R x R; 31) R x R, P x P; 32) R - K 7 would be still more favorable for him.
7. 30…Nb6 A decisive attack.