Slav Defense: Three Knights Variation
The Three Knights Variation of the Slav is 3.Nf3 Nf6 4.Nc3, the main road with both White knights developed. Black chooses between ...dxc4, ...e6 for the Semi-Slav, ...a6 or ...g6, while White aims for e4 or a queenside space grab.
- Moves
- 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3
- ECO
- D15
- Engine
- +0.23 · level (Stockfish 17.1, depth 20)
- Played
- 4,624 games in our lichess sample
- White scores
- 54.0%
Key ideas for both sides
White
- Against 4...dxc4, play 5.a4 to stop ...b5 and recover the pawn later with e3 and Bxc4.
- After 4...e6, 5.Bg5 pins the f6 knight and prepares e3 with steady pressure.
- Against 4...a6, the push c5 locks the queenside and gains space for White.
- Aim for e4 in every line; it is White's main central break against the Slav.
Black
- 4...dxc4 leads to the Czech Variation after 5.a4 Bf5, a solid main line.
- 4...e6 heads for the Semi-Slav with ...Nbd7 and ...Bd6, a very popular choice.
- 4...a6 is the flexible Chebanenko, preparing ...b5 and keeping the bishop free.
- ...g6 is the Schlechter fianchetto, aiming the bishop at d4 from g7.
Plans and pawn structure
This is the main branching point of the Slav. The pawn structure depends on Black's fourth move: ...dxc4 gives up the center for activity, ...e6 builds a solid triangle, ...a6 waits, and ...g6 fianchettoes. White's plans are e4, a4 and queenside pressure with Qb3. Black aims for ...e5 or ...c5 to free the position later, and the c8 bishop's future decides how comfortable Black feels.
What the engine plays from here
Stockfish 17.1 at depth 20 rates the position +0.23: level. Its three top choices for Black:
- +0.23 4...dxc4 5.a4 Bf5 6.e3 e6 7.Bxc4
- +0.23 4...e6 5.Bg5 Nbd7 6.e3 Qa5 7.cxd5
- +0.31 4...a6 5.c5 Nbd7 6.Bf4 Nh5 7.Bd2
Pawns, from White's side.
How it scores on lichess
4,624 rated lichess games reached this position; White scored 54.0%.
Light: White wins. Grey: draws. Dark: Black wins. About the sample.
Where it goes next
- Semi-Slav Defense4...e6 · 15,440 games
- Schlechter Variation4...g6 · 873 games
- Chebanenko Variation4...a6 · 688 games
- Two Knights Attack4...dxc4 · 185 games
- Süchting Variation4...Qb6 · rare
- Chebanenko Variation, Advance System4...a6 · rare
- Czech Variation, Carlsbad Variation, Morozevich Variation4...dxc4 · rare
- Meran Variation, Sozin Variation4...e6 · rare
How to play against it
As Black, choose a system you know. 4...dxc4 with ...Bf5 is solid, 4...e6 heads to the Semi-Slav, and 4...a6 is flexible. Avoid moves that delay development or let White play e4 for free. Know where your c8 bishop belongs before you commit.
Questions
What are the moves of the Slav Defense: Three Knights Variation?
The Slav Defense: Three Knights Variation starts 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3. Its ECO code is D15.
Is the Slav Defense: Three Knights Variation good for White?
Stockfish 17.1 rates the position +0.23 at depth 20, which is level. In 4,624 lichess games from our sample, White scored 54.0%. The main line for both sides; club players need to know their chosen fourth move well.
What is the main idea of the Slav Defense: Three Knights Variation?
Both White knights are out, and Black chooses the structure. The main options are ...dxc4, ...e6, ...a6 and ...g6, each leading to a different Slav system.
What should Black play next?
The engine's first choice is dxc4, with e6 and a6 close behind. 4...dxc4 grabs the pawn and leads to the main lines after 5.a4.
Related lines
- Slav Defense
- Exchange Variation
- Modern Line
- Quiet Variation
- Alekhine Attack
- Schlechter Variation
- How to beat the Slav Defenseguide
Updated October 2026. Sources and method.