Chessy
How to Punish the Nimzowitsch Defense: Kennedy Variation, Linksspringer Variation: Nb4
You've played 1.e4, and Black answers with the offbeat 1...Nc6 — the Nimzowitsch Defense. After 2.d4 e5 3.d5, Black jumps the knight to Nb4. This looks aggressive, but it's a serious positional mistake. With 4.a3 you're already well on your way to a clear advantage. The statistics across over 114,000 games are brutally one-sided: White wins 61.4% of the time, and the engine rates the position at +1.29, a clear edge in your favour. The drill below will show you exactly how to handle Black's most common replies and convert this advantage.
Play the Nimzowitsch Defense: Kennedy Variation, Linksspringer Variation: Nb4 against the engine
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Create a free account →Why 4.a3 Works So Well
After 1.e4 Nc6 2.d4 e5 3.d5, Black's knight on b4 looks active, but it's actually a target. Your move 4.a3 immediately threatens to win a piece with b4-b5 or just c3, kicking the knight. Black's best continuation is simply to retreat: Na6. That's what the engine recommends, and it's also what Black plays in 103,828 games from this position. The knight ends up on a6 — a terrible square — and you get to keep your strong pawn centre. There's no compensation for Black's misplaced piece. You're playing against a knight that will take several moves to become useful again.
Your Best Plan After the Main Reply 4…Na6
In 103,828 games Black chose Na6, which is the engine's recommendation. But don't relax — you still need a plan. The engine's continuation after Na6 is Nc3 d6 Bxa6. That bishop-for-knight trade is excellent for you: you eliminate Black's worst-placed piece and leave him with a damaged pawn structure after …bxa6. If Black instead recaptures with …Bxa6, you have the bishop pair in an open position. Your plan is straightforward: develop naturally (Nf3, Be2 or Bd3, 0-0), keep that space advantage from d5, and play against Black's cramped position. You have a lasting plus that requires patience, not fireworks.
The Three Mistakes Black Makes Most Often
Black often tries to be clever, and it backfires badly. Three moves stand out as clear errors in the database. Nxd5 is a mistake that loses about 2.0 pawns — Black grabs a pawn but White scores 75.3% after it. Qh4 loses about 1.2 pawns; it attacks nothing real and White scores 61.3%. And Nxc2+ is a blunder, losing about 3.3 pawns — a desperate check that just gives up a knight for two pawns, and White scores an astonishing 78.6%. If Black plays any of these, just take the material or defend accurately and the game should be yours. These are not real threats: they are panic moves.
What the Numbers Say About This Position
The database of 114,137 games tells a clear story. White wins 61.4% of the time, Black wins just 35.2%, and draws are rare at 3.4%. Even after Black plays the best move Na6, White still scores 60.3% — so there's no way for Black to escape trouble. The engine's +1.29 rating confirms this is not a fleeting advantage; it's a structural one. Your space, development lead, and Black's awkward knight on a6 add up to a position that's much easier to play as White. If you're looking for a low-theory, high-reward line against the Nimzowitsch, the Kennedy Variation with 4.a3 is exactly that.
Results across 114,137 Lichess games
| Most-played continuation | Games | White wins |
|---|---|---|
| Na6 | 103,828 | 60.3% |
| Nxd5 | 2,509 | 75.3% |
| Qh4 | 1,757 | 61.3% |
| Nxc2+ | 1,444 | 78.6% |
| Nf6 | 1,286 | 70.3% |
| Qf6 | 695 | 66.2% |
Frequently asked questions
Is 4.a3 the best move against the Nimzowitsch Nb4?
Yes, 4.a3 is the engine's recommendation and it's crushing in practice. It immediately challenges Black's knight and forces it to either awkwardly retreat to a6 or make a bad trade. White scores 61.4% from this position across over 114,000 games.
What happens if Black plays Nxd5 after 4.a3?
Nxd5 is a mistake that loses about 2.0 pawns in evaluation. White scores 75.3% after it. You can just recapture on d5 and enjoy a comfortable lead in development and space.
Is Nxc2+ a good check for Black?
No — Nxc2+ is a blunder that loses about 3.3 pawns. It looks flashy but it's just giving up a knight for two pawns. White scores 78.6% after this move. Simply take with your king or defend correctly.
What's the right plan against Black's best move Na6?
After Na6, the engine recommends Nc3 d6 Bxa6. You trade your bishop for the knight on a6, damaging Black's pawn structure if they recapture with the b-pawn. Develop naturally, castle, and use your space advantage to squeeze Black.
How many games feature the Nimzowitsch Defense: Kennedy Variation, Linksspringer Variation: Nb4?
Over 114K Lichess games have reached the Nimzowitsch Defense: Kennedy Variation, Linksspringer Variation: Nb4 position. White wins 61.4%, Black wins 35.2%, with 3.4% draws — based on real rated games.