Ruy Lopez: Closed: what should White play?

In the Ruy Lopez: Closed (ECO C90), White typically proceeds with h3 to secure a small but stable advantage of +0.39. This prophylactic measure prevents Black from placing a piece on g4 and prepares the standard expansion in the center. With 602,000 recorded games, h3 is the most popular choice, appearing in 63.0% of all encounters at this position.

The Strategic Purpose of h3

The move h3 serves as a cornerstone of the Closed Ruy Lopez, primarily aimed at restricting the Black light-squared bishop. By controlling the g4 square, White ensures that the f3 remains unpinned, which is essential for supporting the eventual central thrust of d4. The engine evaluation favors this approach, as it allows White to maintain a flexible setup while preparing the main line h3 Bb7 d4 Re8 Nbd2 Bf8.

Central Confrontation with d4

The most direct alternative is d4, played in 28.1% of games (268,000 instances). While this move challenges the center immediately, it allows Black to complicate the struggle with Bg4, pinning the knight and pressuring the d4 pawn. The engine ranks this as the third-best option with an evaluation of +0.14, leading to lines such as d4 Bg4 Be3 Bh5 Nbd2 d5.

Positional Alternatives and Prophylaxis

White may also opt for slower, more maneuvering approaches. The move d3 appears in 6.7% of games (64,000 recorded) and offers a solid, albeit less ambitious, +0.03 evaluation. Another specialized option is a4, which challenges the queenside structure in 1.4% of games. This move carries a +0.20 evaluation and often leads to the sequence a4 b4 a5 Rb8 Bc4 Bg4, where White seeks to exploit the weakened dark squares on the queenside.