4.Ba4By exchanging the Bishop White could not prove P - Q R 3 to be a lost move, for Black, by retaking with the Q P, obtains open lines for Q and Q B, and in addition to an easy development, retains two Bishops. This is a set-off against a certain weakness in Black's game, which may be found in the fact that after P - Q 4, P x P, White has four pawns to three on the King's side, while his three pawns on the Queen's side are able to hold the four opposing pawns, one of which is doubled. But this weakness can only tell in the end-game, which is too far ahead for practical purposes, and to which it may not come at all. An example of the usual line of play will be found in Game No. 18.
8…O-OIn Capablanca's opinion Black should not castle before White's intentions in the centre have been made clear. It makes a great difference whether White plays his Q P to Q 4 or to Q 3 only. If after 8...Q Kt - R 4; 9 B - B 2, P - B 4 White plays: 10 P - Q 4, his intention is to move his pawn further to Q 5 as soon as Black has castled, and then to attack on the King's wing with Q Kt - Q 2 - B 1 - K 3, P - K Kt 4 and Kt - B 5. For this reason Black should force White to disclose whether he intends to exchange his Q P or to advance it to Q 5. In the latter case Black can refrain from castling altogether and counter-attack on the King's wing, e.g., 10 P - Q 4, Q - B 2; 11 P - K R 3, B - Q 2; 12 Q Kt - Q 2, R - Q B 1; if now: 13 P - Q 5 then P - R 3 followed by P - Kt 4 - Kt 5 gives Black many chances. If on the contrary 13 P x P, then Black need no longer fear an attack on the King's side after he has castled, as his Rooks will have a favourable opportunity for operating on the open Queen's file. However, there is still the disadvantage for Black of having advanced Queen's side pawns, which are liable to attack (P - Q R 4). The game takes a different course when Black exchanges the pawns in the centre. The continuation would then be: 11 ......, Kt - B 3; 12 Q Kt - Q 2, B - Q 2; 13 Kt - B 1, P x P; 14 P x P, P x P; 15 B - Kt 5, Q - Kt 3. It is difficult to decide which side has the advantage. Black has an extra pawn, but White has the initiative. If in Diag. 116, after 8...Castles White plays 9 P - Q 4 at once, Black has an opportunity for the following interesting attack: 9 P - Q 4, B - Kt 5; 10 B - K 3, Kt x K P; 11 B - Q 5, Q - Q 2; 12 B x K Kt, P - Q 4; 13 B - B 2, P - K 5; 14 P - K R 3, B - R 4; 15 Kt - K 5, B x Q; 16 Kt x Q, B x B; 17 Kt x R, R x Kt. White cannot take advantage of his Rooks, as there is no open file, whilst Black threatens to initiate a strong attack with P - B 4. Aljechin has analysed a variation of this line of play, which he thinks leads finally to White's advantage: 12 P x P, Kt - Kt 4; 13 B x Kt, B x B; 14 P - K R 3, B x Kt; 15 Q x B, Kt x P; 16 R x Kt, P x R; 17 B x R, B - B 8; 18 Kt - R 3, Q - Q 7. I doubt that White can win this game.
9.d3In this less aggressive continuation, in which nothing is immediately attempted against Black's centre, White prepares gradually for a King's side attack, as in this game with Kt - Q 2 - B 1 - Kt 3. But Black should obtain time for operations in the centre.
12.a4In many variations of the Ruy Lopez, this advance is always good, if Black cannot avoid exchanging the pawn, because the White Queen's Rook, which only gets into play with difficulty, can either be exchanged or hold the Rook's file. In any case the Black Knight's pawn is weak for the end-game. If, as in the present game, Black can play P - Kt 5, P - R 4 is useless and even doubtful, as the Rook's pawn itself may become weak in the end-game.
12…Bb7This causes the loss of the game. In the Ruy Lopez the Bishop is nearly always needed on the diagonal Q B 1 - K R 6, to prevent a Knight from settling at White's K B 5, which otherwise cannot be repelled except by P - K Kt 3, a most undesirable consummation. The proper continuation would have been P - Kt 5, B - K 3, Q - B 2 and P - Q 4, capturing the Queen's file. Compare note to move 13 in the next game.
14…g6Here is the weakness. White first provides against Black's P - Q 4, and then starts a sharp attack on the King's side.
15…Rad8P - Q 4 at once is not feasible, because of B x Kt.
17.Qc1This brings the Q away from her file, which Black could now secure by P - Q 4, followed by P x P.
17…Rfe8The proper continuation is the one outlined in the note above.
18.h3White has now ample leisure to prepare the advance of his K B P.
23…Qe7Black seeks salvation in exchanges, which White, of course, tries to avoid, having good prospects of driving home his attack. His pieces are concentrated on the King's side, whilst the Black forces are scattered, and unable to get back in time for the defence. Moreover, it is likely that the weakness at Black's K R 3 and K B 3 will prove fatal as the Black K B is exchanged.
26…g5White was threatening to play Kt - Kt 4 with P x P and Kt - R 6.
28…Qxf6One of the attacking Knights is eliminated. But there is another, which forces the entry at K B 6 and K Kt 6.
29.h4To gain access for the White Queen at K R 6. If Black captures there follows: 30 Kt - R 5, Q - Q 1; 31 Q - R 6, Q - B 1; 32 Kt - B 6 ch, an instructive example of the weakness created by P - K Kt 3.
31.f6All this is easy to understand.
36.exf5+The conclusion might be: K - R 2; 37 B - R 5, P x P; 38 Q x P, R - K Kt 1; 39 B - Kt 6 ch, P x B; 40 Q - R 4 mate.
Edward Lasker, Chess Strategy (1921) · Public domain · source