6.d4In a game between Riga and Berlin P x P was tried for the first time, a bold venture which anticipates White's desire to open the King's file. After 7 R—K 1 Black can defend the Kt by P—Q 4, but after 8 Kt x P White threatens again to win the Kt by P—K B 3, besides attacking the Q Kt a second time. However, Black has a surprising answer in readiness. He initiates a violent counter attack which keeps White busy until Black, by castling, escapes the dangers of the double pin. (Compare Game No. 17.)
8.a4This gives Black an opportunity of disposing of his Q Kt by exchanging it, thereby enabling him to round off his pawn position by P—Q B 4, at the same time threatening to cut off the Bishop by P—B 5. 8 P x P followed by P—B 3 is the natural continuation, as shown in the first part of this book, because the Bishop, retreating to B 2, can operate on a useful diagonal.
8…Nxd4Q R—Kt 1 would not be so good, because White obtains an open file for his Rook. The move in the text is an absolutely valid defence, as was proved by Schlechter in his match against Lasker.
10.Nc3P x P and P—B 3 seems a more natural continuation.
10…Nxc3Not P x Kt, on account of B x P.
12…Be7in order to castle in reply to B—R 4.
13.Qf3Here White should have got back his second pawn by P x Q P. If then 13...P—B 5; 14 B—R 4, Castles; 15 P x P, B x P, White plays P—Q B 3, providing a retreat for his R or B. After the move in the text this manœuvre becomes impossible, because the B after P—B 3 can be attacked twice but has lost the support of the Queen.
16.Ba2Now the Bishop is hemmed in permanently; in other words, Black is a piece up and must win easily. Therefore 16 B—R 4 was compulsory in order to get at any rate three pawns for the piece, thus: 16...B—Q 2; 17 Q x P, R x R; 18 P x R, B x B; 19 Q x P.
22.Kh1In order to answer B x Q P by 23 B—K 3 and P—R 7, 22...Q x P is not feasible because of Q x P.
26…Be4The sequel forms an instructive example of how superior development can afford winning chances even when there is no immediate prospect of material gain. The opposing pieces are gradually constricted until the defending lines are weakened by compulsory pawn moves. In the present position Black quietly sets to work to bring his Bishops to bear on the White King.
29…Bh4Being probably short of time, Black makes a few irrelevant moves. If his aim was not the opening of the K Kt file but the subsequent sacrifice of the Queen, he might have played Q—Kt 7 at once, followed by Q—Kt 4.
37.Rg1Otherwise White might embark upon a counter attack, beginning while P—Kt 4. Now this is impossible on account of R—Kt 3.
39.Qh5After the exchange of Queens, Black would win easily by R—Kt 7. 39 B—R 2 also fails on account of Q x Q; 40 R x Q, R—Kt 7; 41 B—Kt 3, B—Q 6!; 42 R—K 5, B x P, and the passed pawn costs a Rook. With the text move, White provokes the sacrifice of the Queen at Kt 8, apparently not seeing the fine continuation at Black's disposal on the forty-first move.
41.g4Compulsory. B—Kt 1 would be followed by R—Q B 8, etc.
41…Bc1There might follow 42 K—Kt 3, P—Kt 3; 43 Q—R 4, B x P ch; 44 K x B, P—Kt 4 ch, and so on. 41...B—Q 3 would have given White a little respite, though his game would still have been hopeless after P x P and R—K 8.
Edward Lasker, Chess Strategy (1921) · Public domain · source