Playing Against the Sokolsky Opening: a5

After 1.b4 a5 2.b5, White has gained space on the queenside but has weakened the b4-square and spent a tempo on a pawn that now sits on b5. Meanwhile, you have already staked a claim on the a5-square and can now develop normally. The engine's evaluation of +0.13 tells you the position is essentially equal — that small number is not a real advantage for anyone. From your perspective as Black, you are fine. The key is not to panic or play too aggressively trying to 'prove' that 1.b4 is bad. Solid development, central control, and a bit of patience are all you need.

The best move according to Stockfish is 2...d5. This immediately stakes a claim in the centre, the one thing White's wing-pawn opening has neglected. After 2...d5, a natural continuation is 3.Nf3 Nd7 4.Bb2 — White develops the bishop to a useful diagonal and prepares to castle. At that point Black has a solid, classical centre and can follow up with e6, Ngf6, and a normal development plan. The statistics back this up: in the 4,551 games where Black played 2...d5, White scored just 50.9% — the lowest score among the top five most popular moves besides one exception.

Here is how Black's most common moves perform across the Lichess database (75,897 games): - 2...c6 (31,528 games) – White scores 52.4%. Very popular but gives White his best results. - 2...b6 (14,710 games) – White scores 50.2%. Almost equal, and a reasonable choice if you want to fianchetto on the queenside. - 2...a4 (9,372 games) – White scores 52.6%. Pushing the a-pawn again looks aggressive but White scores well against it. - 2...d5 (4,551 games) – White scores 50.9%. The engine's pick and statistically strong. - 2...Nf6 (4,519 games) – White scores just 48.0%. That is the only move where White scores below 50% — which means 2...Nf6 outperforms even d5 in practical play! Developing the knight and preparing to strike in the centre is a perfectly good alternative. - 2...e5 (3,108 games) – White scores 50.9%. A solid central move, equally as good as d5 statistically. Overall, d5 and Nf6 stand out as your best bets.

Because the position is equal, the mistakes here are subtle — but they can tilt the game in White's favour. Avoid these: - Playing 2...c6 without a plan. It's the most common move but gives White 52.4% wins. If you trade on b5, you open the a-file for White's rook and may end up with a backward d-pawn. - Pushing 2...a4 too early. White can respond with Bb2 and later challenge the a4-pawn with Nc3 or a3. The pawn can become a target. - Neglecting the centre. Remember, White has no central presence yet. If you develop only on the wings (e.g. b6 followed by Bb7), White can play d4 and claim space. Your main priority is occupying or attacking d5 and e5.