Nimzowitsch Defense: Kennedy Variation, Paulsen Attack
The Paulsen Attack of the Kennedy Variation is 3.dxe5 Nxe5 4.Nf3, where White hits the e5 knight at once. White develops with tempo, while Black chooses between ...d6, keeping the knight in the center, or ...Nxf3+, giving White doubled f-pawns.
- Moves
- 1.e4 Nc6 2.d4 e5 3.dxe5 Nxe5 4.Nf3
- ECO
- B00
- Engine
- +0.65 · a slight edge for White (Stockfish 17.1, depth 20)
- Played
- 719 games in our lichess sample
- White scores
- 55.5%
Key ideas for both sides
White
- Develop with Nc3 and Bf4 to pressure the e5 knight, as in the top engine line, then Qd2.
- After ...Nxf3+, recapture gxf3 and use the open g-file with Rg1 against the g7 pawn.
- Answer ...Ng6 with Bg3, keeping the bishop on the diagonal toward c7 and d6.
- Consider castling queenside once Qd2 is in, since the d-file is half open for your rook.
Black
- Play 4...d6, the engine's choice, to keep the knight centralized and open the c8 bishop.
- Answer Bf4 with ...Ng6, as in the engine line, to gain time on the bishop.
- If you trade on f3, play ...Qf6 and ...Bb4 to pin the c3 knight and hit the queenside.
- Avoid early queen moves without the trade, which give White more time to develop.
Plans and pawn structure
White uses Nf3 to hit the e5 knight. If Black plays ...d6, White develops with Nc3, Bf4 and Qd2, Black responds with ...Nf6, ...Ng6 and ...Be7, and White keeps a small edge in space. If Black trades with ...Nxf3+, White gets doubled f-pawns but an open g-file for the rook and extra control of e4 and g4. Black then plays ...Qf6, ...Bb4 and ...Ne7 and aims at the damaged pawns.
What the engine plays from here
Stockfish 17.1 at depth 20 rates the position +0.65: a slight edge for White. Its three top choices for Black:
- +0.65 4...d6 5.Nc3 Nf6 6.Bf4 Ng6 7.Bg3
- +0.87 4...Nxf3+ 5.gxf3 Qf6 6.Nc3 Bb4 7.Bd2
- +0.90 4...Qf6 5.Nc3 Nxf3+ 6.gxf3 Bb4 7.Bd2
Pawns, from White's side.
How it scores on lichess
719 rated lichess games reached this position; White scored 55.5%.
Light: White wins. Grey: draws. Dark: Black wins. About the sample.
How to play against it
Black, play 4...d6 and keep the knight. If you trade on f3, be ready for Rg1 and pressure on g7. White, develop with Nc3 and Bf4 and keep chasing the knight; every tempo helps your lead in development. Then add Qd2.
Questions
What are the moves of the Nimzowitsch Defense: Kennedy Variation, Paulsen Attack?
The Nimzowitsch Defense: Kennedy Variation, Paulsen Attack starts 1.e4 Nc6 2.d4 e5 3.dxe5 Nxe5 4.Nf3. Its ECO code is B00.
Is the Nimzowitsch Defense: Kennedy Variation, Paulsen Attack good for White?
Stockfish 17.1 rates the position +0.65 at depth 20, which is a slight edge for White. In 719 lichess games from our sample, White scored 55.5%. A comfortable choice for White players who like quick development, and Black needs accurate, patient defense.
What is the main idea of the Nimzowitsch Defense: Kennedy Variation, Paulsen Attack?
White develops with tempo against the e5 knight. Black keeps it with ...d6, or trades on f3 and gives White doubled pawns plus an open g-file.
What should Black play next?
The engine's first choice is d6, with Nxf3+ and Qf6 close behind. 4...d6 supports the knight and lets the c8 bishop join the game.
Related lines
Updated October 2026. Sources and method.