Queen's Gambit Declined: Semi-Slav, Koomen Variation

1. d4 d5 2. c4 e6 3. Nc3 c6 4. Nf3 dxc4 5. e3 b5 6. a4 Bb4 7. Bd2 Qe7

Queen's Gambit Declined: Semi-Slav, Koomen Variation after 1. d4 d5 2. c4 e6 3. Nc3 c6 4. Nf3 dxc4 5. e3 b5 6. a4 Bb4 7. Bd2 Qe7 87654321abcdefgh

The Queen's Gambit Declined: Semi-Slav, Koomen Variation is a chess opening classified as ECO D31, reached after 1. d4 d5 2. c4 e6 3. Nc3 c6 4. Nf3 dxc4 5. e3 b5 6. a4 Bb4 7. Bd2 Qe7. It is a line of the Queen's Gambit Declined. White is to move.

This exact move order didn't appear in our sample of 12.6 million Lichess games: it's a rare line.

Engine evaluation: +0.38 (Stockfish, depth 34; best line 8. axb5 Bxc3 9. Bxc3 cxb5 10. Bd2 Nf6)

ECO
D31
Moves
14 plies
FEN
rnb1k1nr/p3qppp/2p1p3/1p6/PbpP4/2N1PN2/1P1B1PPP/R2QKB1R w KQkq - 3 8
PGN
1. d4 d5 2. c4 e6 3. Nc3 c6 4. Nf3 dxc4 5. e3 b5 6. a4 Bb4 7. Bd2 Qe7

Analyse with Stockfish · Board image (SVG) · Open on Lichess

Comes from

Semi-Slav Defense: Noteboom Variation 1. d4 d5 2. c4 e6 3. Nc3 c6 4. Nf3 dxc4

More Queen's Gambit Declined lines (all)

Opening names and moves from the Lichess openings dataset; statistics from the Lichess open database, 2026-09 (CC0), sample of 12.6 million games, bots excluded; evaluations from Lichess cloud analysis (all CC0). Master games from The Week in Chess #920–#1664 by Mark Crowther, used with permission.