The Three Knights Variation is a variation of the Queen's Gambit Declined, catalogued as ECO D37. The line runs 1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Nf3 Be7 5. e3 O-O, reaching the position shown below after 10 half-moves.
Both sides have pawns in the centre (White on d4, Black on d5), and one pawn capture is available, so the structure has not settled yet. Development is level at two minor pieces each. It is White to move after five moves. Black has castled while White’s king is still uncommitted.
On the Queen's Gambit Declined generally: A solid and respected response to the Queen's Gambit. Black maintains a strong central presence.
You can play through this variation move by move in your browser — Learn mode walks the line with an explanation at each step, and Drill mode replays it from memory so you find out whether you actually know it. No account is required.
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The Three Knights Variation goes 1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Nf3 Be7 5. e3 O-O. It is a variation of the Queen's Gambit Declined and is catalogued as ECO D37.
The Three Knights Variation is ECO D37. ECO codes group openings by their move order, so nearby codes cover closely related lines of the Queen's Gambit Declined.
Stockfish evaluates the position after 1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Nf3 Be7 5. e3 O-O at +0.05 at depth 18, which is balanced. Engine evaluation is only a starting point — at club level the practical value of a line is mostly about whether you know its plans better than your opponent does.
Both sides have pawns in the centre (White on d4, Black on d5), and one pawn capture is available, so the structure has not settled yet. Development is level at two minor pieces each. It is White to move. Black has castled while White’s king is still uncommitted.