Chess Openings Lab
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Sicilian Defense: Kan Variation, Knight Variation

The Kan Knight Variation is 5.Nc3, where White develops the queen's knight instead of Bd3 or c4. Black often answers with ...b5 for queenside space, while White can set up Be3, f3 and Qd2 or a calmer Bd3 plan.

Moves
1.e4 c5 2.Nf3 e6 3.d4 cxd4 4.Nxd4 a6 5.Nc3
ECO
B43
Engine
+0.20 · level (Stockfish 17.1, depth 20)
Played
2,460 games in our lichess sample
White scores
47.5%

Key ideas for both sides

White

  • Against ...b5, Be3, f3 and Qd2 prepare long castling, as the top engine line shows.
  • Against ...Qc7, Bd3 and O-O give a quieter setup with f4 or Qe2 ideas later.
  • After ...Nc6, Nxc6 leaves Black with doubled c-pawns, then Bd3 and Re1 support an e5 push.
  • Watch the knight on c3. Once ...b4 is possible, e4 may need extra cover from Bd3 or f3.

Black

  • 5...b5 gains space at once and prepares ...Bb7 against e4, then ...b4 to kick the c3 knight.
  • 5...Qc7 covers e5 and c7 and keeps ...Nc6 and ...Nf6 for the next moves.
  • 5...Nc6 invites Nxc6 bxc6, after which ...d5 builds a sturdy center with two c-file pawns.
  • After ...Nxd4 Bxd4, the white bishop is strong, so finish development before opening lines.

Plans and pawn structure

With the knight on c3, White is ready for a fast setup. Against ...b5, White plays Be3, f3 and Qd2, castles long and pushes g4 and h4. Black's answer is speed on the other wing: ...Bb7, ...Nc6 and ...b4 to drive the c3 knight away from e4. Against ...Qc7, White prefers Bd3 and short castling, and the game is slower. After ...Nc6 and Nxc6, Black's ...d5 and White's e5 decide the central structure.

Where the engine's main line heads: Open Sicilian: White traded the d-pawn for Black's c-pawn. An Open Sicilian: White traded the d-pawn for Black's c-pawn. White has a lead in development and the d-file, Black has the half-open c-file and two central pawns.

What the engine plays from here

Stockfish 17.1 at depth 20 rates the position +0.20: level. Its three top choices for Black:

  1. +0.20 5...b5 6.Be3 Bb7 7.f3 Nc6 8.Qd2
  2. +0.32 5...Qc7 6.Bd3 Nc6 7.Nxc6 bxc6 8.O-O
  3. +0.41 5...Nc6 6.Nxc6 bxc6 7.Bd3 d5 8.O-O

Pawns, from White's side.

How it scores on lichess

2,460 rated lichess games reached this position; White scored 47.5%.

1200–159947.3%
1600–199948.4%
2000 and up46.8%

Light: White wins. Grey: draws. Dark: Black wins. About the sample.

Where it goes next

How to play against it

With Black, choose ...b5 for active queenside play or ...Qc7 for a calmer setup. Do not delay development with extra pawn moves, since White can push e5 or f4 quickly. If White plays f3, a well-timed ...b4 and ...d5 strike before White's king walks to c1.

Other lines with this name

The lichess opening list also files this line under the same name, though it reaches a different position: 1.e4 c5 2.Nf3 e6 3.d4 cxd4 4.Nxd4 a6 5.Nc3 b5 6.g3 Bb7 7.Bg2.

Questions

What are the moves of the Sicilian Defense: Kan Variation, Knight Variation?

The Sicilian Defense: Kan Variation, Knight Variation starts 1.e4 c5 2.Nf3 e6 3.d4 cxd4 4.Nxd4 a6 5.Nc3. Its ECO code is B43.

Is the Sicilian Defense: Kan Variation, Knight Variation good for White?

Stockfish 17.1 rates the position +0.20 at depth 20, which is level. In 2,460 lichess games from our sample, White scored 47.5%. A practical choice for White players who like direct development; Black should know the ...b5 and ...Qc7 setups.

What is the main idea of the Sicilian Defense: Kan Variation, Knight Variation?

White develops with Nc3 and prepares either a quick attack with Be3 and Qd2 or a calm setup with Bd3. Black uses ...b5 or ...Qc7 to gain space and pressure e4.

What should Black play next?

The engine's first choice is b5, with Qc7 and Nc6 close behind. 5...b5 gains queenside space and prepares ...Bb7.

Updated October 2026. Sources and method.