Nimzowitsch Defense: Kennedy Variation, Riemann Defense: what should White play?

In the Nimzowitsch Defense: Kennedy Variation, Riemann Defense, White's most effective and popular continuation is e5. This move, played in 49.4% of recorded games, carries an engine evaluation of +1.24 and yields a 61.0% win rate for White. By advancing the pawn to e5, White immediately challenges the f6 and seizes a significant space advantage in the center.

The strategic impact of e5

The move e5 is the theoretical main line of this variation, appearing in 28,000 games. It forces the black knight to relocate, typically resulting in the sequence e5 Ng8 Be3 Bb4 Qd2 Nge7. By driving the knight back to g8, White disrupts Black's development and prepares to solidify the center with e3 and d2, often eyeing long queenside castling to support the aggressive pawn structure.

Development with Nf3

The second most common choice is Nf3, which has been played in 35.5% of the 51,565 recorded games at this position. While less forcing than the pawn advance, it maintains a solid +0.61 evaluation and a 56.8% win rate. This move often leads to the line Nf3 Bb4 Bd3 d5 e5 Ne4, where White focuses on piece activity and king-side safety before committing to the central expansion.

Alternative approaches and sidelines

White may also consider Bc4, a move seen in 3.8% of games with a 55.4% success rate. This development targets the f7 weakness but allows Black to counter-strike in the center via Bc4 Bb4 e5 d5 exf6 dxc4. Rarer options include Bd2 and a3, though these are significantly less frequent, representing only 1.0% and 0.4% of the database respectively. While a3 carries a high win rate of 59.7%, it is largely a prophylactic measure against the b4 pin rather than a direct challenge to Black's setup.