The Main Line is a variation of the Semi-Slav Defense Accepted, catalogued as ECO D44. The line runs 1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 e6 5. Bg5 dxc4, reaching the position shown below after 10 half-moves.
White holds the centre with pawns on d4. White is ahead in development, with three minor pieces out to Black's one, and Black is up a pawn of material. It is White to move after five moves. Black has doubled pawns on the c-file.
On the Semi-Slav Defense Accepted generally: ECO D44. A chess opening with 1 known variation.
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See all 6 Semi-Slav Defense Accepted variations →
The Main Line goes 1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 e6 5. Bg5 dxc4. It is a variation of the Semi-Slav Defense Accepted and is catalogued as ECO D44.
The Main Line is ECO D44. ECO codes group openings by their move order, so nearby codes cover closely related lines of the Semi-Slav Defense Accepted.
Stockfish evaluates the position after 1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 e6 5. Bg5 dxc4 at +0.55 at depth 18, which is a slight pull for White, within normal opening margins. 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.
White holds the centre with pawns on d4. White is ahead in development, with three minor pieces out to Black's one, and Black is up a pawn of material. It is White to move. Black has doubled pawns on the c-file.