Polish Opening, with d5: what should Black play?

In the Polish Opening (ECO A00) with d5, the most effective response for Black is e5, which challenges the center and exploits the slight weakening of the kingside caused by White's early f6. This move is played in 88.6% of the 19,194 recorded games at this position, carrying an engine evaluation of -0.21. By establishing a presence on e5, Black aims to neutralize the influence of the b2 and prepare for rapid development.

The dominance of e5

The move e5 is the overwhelming choice in master-level play, appearing in 18,000 recorded games. It directly contests the center and prepares to meet White's typical setup. The engine prefers this continuation because it forces White to address the tension immediately, often leading to the main line e5 e3 c6 d4 e4 c4. Despite the engine's slight preference for Black, White maintains a 52.9% scoring rate from this position, suggesting that the resulting structures remain highly competitive.

Development alternatives

While e5 is the standard, other moves focus on slower piece coordination. The move e6 is the second most popular choice, played in 3.0% of games, leading to a more solid but passive structure where White scores 54.5%. Another option is Nc6, which carries an engine evaluation of +0.26. This move aims for active piece play but allows White a higher scoring percentage of 59.5% through the continuation Nc6 c4 d4 Nf3 e5 e3.

Probing the queenside

Black occasionally employs a5 to immediately challenge the b4 pawn. Although played in only 0.6% of games, it forces White to decide between defending the pawn or pushing forward with b5. The engine evaluates this at +0.29, leading to lines such as a5 b5 Nd7 e3 Nb6 d4. This approach is less about central control and more about disrupting White's queenside expansion early in the opening.