Anti-Marshall: 8.a4 is variation 5 of 6 in the Ruy Lopez course, a intermediate opening course for White (ECO C88). It runs 26 moves and begins 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 …. If Black castles on move 7, 8.c3 allows the Marshall Attack, a famous pawn sacrifice (8...d5). White avoids it with 8.a4, putting pressure on b5, and plays a slow d3 set-up. In the lesson every move is explained on a board and then drilled; it is free.
Move by move
1. e4 – Takes the centre.
1... e5 – Black claims an equal share.
2. Nf3 – Develops and attacks e5.
2... Nc6 – Defends e5.
3. Bb5 – Pressure on the e5 pawn's defender.
3... a6 – Challenges the bishop.
4. Ba4 – Keeps the bishop.
4... Nf6 – Develops and attacks e4.
5. O-O – Castles.
5... Be7 – The Closed Defence.
6. Re1 – Defends e4 and threatens Bxc6 and Nxe5.
6... b5 – Kicks the bishop.
7. Bb3 – The bishop takes the a2-g8 diagonal.
7... O-O – Black castles, preparing the Marshall Attack if White plays c3.
8. a4 – The Anti-Marshall: attacks b5 at once, so Black must spend a move on it instead of ...d5.
8... Bb7 – Develops toward e4; b5 is held indirectly because axb5 axb5 Rxa8 Qxa8 leaves Black's queen active on the long diagonal.
The lesson goes on for 10 more moves, each with its explanation.
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