Polish Defense: what should White play?

In the Polish Defense (ECO A40), reached after Black responds on the flank to the queen's pawn, White's most direct and principled choice is e4. Occupying the center gives White an engine evaluation of +1.03 and represents the most common response, played in 51.4% of recorded games (800K recorded). This advance establishes an ideal classical pawn center, challenging Black to justify the early queenside expansion without central control.

The central response with e4

Advancing e4 immediately claims the e4 square alongside d4, leaving White with a broad central presence and a White score of 52.4%. Black typically must reckon with the exposed state of the b5 pawn. An illustrative engine line demonstrates how play develops when Black attempts to consolidate: e4 a6 Nd2 e6 a4 b4, where White effectively challenges the queenside structure while retaining central superiority.

Developing moves: Nf3 and Nd2

Players seeking to bypass early sharp pawn confrontations often select Nf3, which accounts for 28.1% of recorded games (437K recorded) and delivers a White score of 54.3% with an evaluation of +0.63. The engine illustrates calm piece deployment in Nf3 d5 e3 a6 b3 Nf6. Alternatively, the engine ranks Nd2 second overall with a +0.99 evaluation, leading toward the variation Nd2 e6 e4 b4 Bd3 a5, where the knight supports the center while keeping the c-pawn unobstructed.

Structural alternatives: a4 and e3

White can also challenge the flank directly via a4, chosen in 1.5% of games (24K recorded, scoring 52.3%, +0.67), where a4 b4 e4 e6 Nf3 Nf6 immediately displaces the b-pawn. The solid e3 is another frequent choice, seen in 19.0% of games (295K recorded, scoring 51.8%, +0.47) and continuing along the sequence e3 a6 Nf3 e6 Nbd2 d5.