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

ECO D31

The Queen's Gambit Declined: Semi-Slav, Koomen Variation is a chess opening line in the Queen's Gambit Declined complex, 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 catalogued under code D31 in the Encyclopaedia of Chess Openings (ECO).

The defining move Qe7 is chosen by Black on move 7.

The Queen's Gambit Declined: Semi-Slav, Koomen Variation is a line of the Queen's Gambit Declined. The Queen's Gambit Declined is a chess opening that begins 1.d4 d5 2.c4 e6. Read the complete Queen's Gambit Declined guide: what it is, how to reach it, its main variations, how to play against it, and its history.

More ECO D31 openings

• Semi-Slav Defense — 1.d4

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Every chess term used here is defined in the chess terms glossary. Browse all opening courses or the full ECO code index.