Nimzowitsch Defense: Kennedy Variation, Keres Attack: what should White play?

In the Nimzowitsch Defense: Kennedy Variation, Keres Attack, White achieves the most critical advantage by playing f4. This aggressive advance immediately challenges the centralized knight on e5, yielding an engine evaluation of +1.40 and a 59.2% score for White across 71K recorded games. While the quieter developing continuation Nf3 is the most frequent choice at 40.8% of recorded games (120K games), f4 offers a direct bid for central control and space.

The Aggressive Thrust with f4

Advancing the f-pawn with f4 strikes at Black's only active minor piece in the center. An illustrative engine continuation runs f4 Nc6 e5 Ng8 Bc4 d6, where White gains considerable tempo by chasing Black's knights backward while establishing advanced central pawns. Although played in 23.9% of the 295,319 games recorded at this position, it boasts White's highest score among the main options.

Natural Development with Nf3

Players seeking a calmer setup often prefer Nf3, which accounts for 40.8% of recorded games with a solid 55.7% scoring performance and an engine evaluation of +0.53. In the illustrative variation Nf3 d6 Bf4 Ng6 Bg3 Be7, White avoids early structural commitments and develops smoothly along classical opening principles.

Bishop Developments and Alternatives

White can also target the knight or develop the dark-squared bishop immediately. The move Bf4 appears in 20.8% of games (62K recorded, scoring 53.3%, eval +0.29), followed illustratively by Bf4 Ng6 Bg3 Bb4 Qd3 O-O. Alternatively, Bg5 pins the f6-knight and scores 52.6% over 43K recorded games (eval +0.19), leading into Bg5 h6 Bxf6 Qxf6 Nd5 Qd8. White also holds the option of the subtle a3, evaluated at +0.30, with the illustrative line a3 Bc5 Qe2 O-O Be3 Qe7.