Caissa Codex
D37

Queen's Gambit Declined: Harrwitz Attack, Two Knights Defense

Chess diagram: Queen's Gambit Declined: Harrwitz Attack, Two Knights Defense after 6…Nbd7

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Statistics from Lichess

164,856 games: White 49.8% / Draw 6.6% / Black 43.6%

The moves played next. Pick one to see it on the board.
Next moveGamesWhite / Draw / BlackW / D / B
43,20943K
Queen's Gambit Declined: Harrwitz Attack, Two Knights Defense, Blockade Line 31,54332K
20,56621K
17,89118K
16,18316K
14,64815K
8,1978,197
5,3005,300

Rated Lichess games between players rated 1600 to 2500, from the Lichess opening explorer, updated Oct 27, 2026

Engine evaluation

+0.25 The position is about equal

Best play: 7. c5 Nh5 8. Bd3 b6 9. b4 a5 10. a3 Nxf4 11. exf4 c6

Stockfish 19, depth 30, after the line's last move. Scores are in pawns, from White's side.

Overview

Queen's Gambit Declined: Harrwitz Attack, Two Knights Defense (ECO D37, Closed & Semi-Closed Games) is a declined gambit in the Queen's Gambit Declined: Harrwitz Attack, reached after 1. d4 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 Be7 5. Bf4 O-O 6. e3 Nbd7 (6 moves).

In 164,856 rated Lichess games between players rated 1600 to 2500, White won 49.8%, Black 43.6% and 6.6% were drawn. White's most played move here is 7. Bd3, in 26% of those games.

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How to play against the Queen's Gambit Declined: Harrwitz Attack, Two Knights Defense

7. c5 (Queen's Gambit Declined: Harrwitz Attack, Two Knights Defense, Blockade Line) scores best for White: 57.6%, with White winning 53.8% and Black 38.7% of 32K games. The most played answer, 7. Bd3, scores lowest: 50.2% in 43K games. Stockfish's first choice is also 7. c5.

Main answers: those played in at least 5% of these games. Score: White's wins plus half the draws, in rated Lichess games between players rated 1600 to 2500. How to play against other popular openings

Other lines from the same position

Instead of 5…O-O 6. e3 Nbd7, the position after Queen's Gambit Declined: Harrwitz Attack also goes on to:

Transpositions

From here, a move transposes into another named line:

Cite this page

Caissa Codex. “Queen's Gambit Declined: Harrwitz Attack, Two Knights Defense (D37)”. Lichess data as of 27 Oct 2026. https://chesscodex.org/openings/queens-gambit-declined-harrwitz-attack-two-knights-defense

https://chesscodex.org/openings/queens-gambit-declined-harrwitz-attack-two-knights-defense