37. Anti-Marshall 8.a4 Rb8
8...Rb8 defends b5 with the rook. White immediately opens the a-file with 9.axb5 axb5 and controls it with the a1-rook, then plays d3 and c3 as in a Closed Ruy Lopez.
1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.Re1 b5 7.Bb3 O-O 8.a4 Rb8 9.axb5 axb5 10.d3 d6 11.c3
Move by move
- 1.e4 – White takes the centre and opens the diagonals for the queen and the f1-bishop. In the Ruy Lopez this pawn will often be at the heart of the fight: Black will attack it with ...Nf6 and, in the Open Variation, will even capture it with ...Nxe4.
- 1...e5 – Black answers symmetrically: it contests d4 and f4, prevents e4-e5 and frees the f8-bishop. From here White will build the whole Ruy Lopez on pressure against this pawn.
- 2.Nf3 – Develops the knight with a direct attack on the e5 pawn, which now has to be defended. The knight also prepares kingside castling and supports a future d2-d4 push.
- 2...Nc6 – Defends e5 while developing a piece and controlling d4. This very knight, the only defender of e5, will be the target of White's next move.
- 3.Bb5 – The Ruy Lopez: the bishop attacks the c6-knight, the defender of e5. There is no immediate threat yet (Bxc6 dxc6 Nxe5 Qd4 regains the pawn), but the pressure on c6 will last throughout the opening.
- 3...a6 – Morphy's move: it asks the bishop to decide right away. After 4.Ba4 Black can break the pin with ...b5 whenever it likes; after 4.Bxc6 it gets the bishop pair.
- 4.Ba4 – The bishop retreats but keeps the pressure on c6: the threat of Bxc6 followed by Nxe5 will come back once White has castled. Black can break the diagonal with ...b5 whenever it wants.
- 4...Nf6 – Develops the knight attacking e4. This is the main move: it leads to the Closed Ruy Lopez with ...Be7 or to the Open Variation with ...Nxe4.
- 5.O-O – Castles without defending e4: if Black takes it with ...Nxe4, White regains it with Re1 or d4, exploiting the black king still in the centre.
- 5...Be7 – The Closed Ruy Lopez: Black does not take e4 and develops the bishop to castle. From e7 it protects the king and leaves the f6 square free for the knight.
- 6.Re1 – The rook defends e4. Now White really threatens Bxc6 dxc6 Nxe5, because the recovery ...Qd4 no longer works with e4 protected.
- 6...b5 – Black drives the bishop away from a4 and solves the threat on c6. It gains space on the queenside, but the b5 pawn will become a target for a2-a4.
- 7.Bb3 – The bishop retreats to the a2-g8 diagonal, from where it aims at f7 and supports a future d4 push. It is the natural square in the Closed Ruy Lopez.
- 7...O-O – Black castles before deciding the centre: if White plays 8.c3, Black can answer 8...d5, the Marshall Attack. That is why White has the Anti-Marshall moves available.
- 8.a4 – The most used Anti-Marshall: instead of c3 White attacks b5 at once. If Black plays 8...d5, the tension on the queenside makes the gambit less effective.
- 8...Rb8 – The rook defends b5 and leaves the c8-bishop free.
- 9.axb5 – White exchanges on b5 and opens the a-file, which now belongs to the a1-rook.
- 9...axb5 – Black recaptures. With the rook on b8 the a-file is in White's hands.
- 10.d3 – Defends e4 and prepares the development of the queenside.
- 10...d6 – After the a-file opens, Black supports e5 and frees the c8-bishop, which is not yet developed.
- 11.c3 – Gives the bishop the retreat to c2 and prepares Nbd2. A possible ...b4 can now be met with cxb4.
How to exploit the position
White controls the a-file, Black has the rook on b8 defending b5.
- Use the a-file: the a1-rook can enter on a7 or double with the queen.
- Manoeuvre the knight with Nbd2-f1-g3 as in the Closed Ruy Lopez.
- Prepare d4 when the pieces are ready.
- The b5 pawn can become a target: Na3 and Bd5 attack it.
Master tips
The open a-file
After 9.axb5 axb5 the a-file is White's, because the black rook has moved to b8.