The Harrwitz Attack, Two Knights Defense is a variation of the Queen's Gambit Declined, catalogued as ECO D37. The line runs 1. d4 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 Be7 5. Bf4 O-O 6. e3 Nbd7, reaching the position shown below after 12 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 three minor pieces each. It is White to move after six 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.
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The Harrwitz Attack, Two Knights Defense goes 1. d4 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 Be7 5. Bf4 O-O 6. e3 Nbd7. It is a variation of the Queen's Gambit Declined and is catalogued as ECO D37.
The Harrwitz Attack, Two Knights Defense 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 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 Be7 5. Bf4 O-O 6. e3 Nbd7 at +0.21 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 three minor pieces each. It is White to move. Black has castled while White’s king is still uncommitted.