Why the Semi-Slav Defense is worth training
1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6.The Semi-Slav Defense arises after 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6. Black supports d5 with both the c-pawn and the e-pawn and forms a solid triangle in the center. The cost is the bishop on c8, which is shut in behind e6. Black often frees it with ...dxc4 followed by ...b5 and ...c5, or with the central break ...e5.
Chessmate has a Semi-Slav Defense course for White and a Semi-Slav Defense course for Black. The White course has twelve lines built around the Catalan-style 5.g3, and the Black course has sixteen lines against the Meran, the Anti-Meran, the Moscow and Anti-Moscow, and White's other fifth moves.
The Ng5 and Nxe6 sample line for White
13.Ne4, White has given a piece, but Black's king is stuck on e7 and the knight eyes d6 and f6.In the White sample line, White plays 5.g3 and develops the bishop on the long diagonal instead of rushing to win back c4. After 5...dxc4 6.Bg2 Nbd7 7.O-O b5, Black holds the extra pawn, and White builds a broad center with 8.e4 Bb7 9.e5.
After 9...Nd5, White plays 10.Ng5, which clears the long diagonal and creates threats against e6 and h7. After 10...h6, White sacrifices the knight with 11.Nxe6 fxe6, checks with 12.Qh5+, and after 12...Ke7 brings the other knight to the center with 13.Ne4. White's initiative is the compensation for the material.
The Meran sample line for Black
14...Bb7, Black is a pawn up, and the queen on b6 and the pawn on d4 hold the center.The Black sample line is the Classical Meran. After 5.e3 Nbd7 6.Bd3, Black takes with 6...dxc4, so White's bishop must spend a tempo recapturing. After 7.Bxc4 b5 8.Bd3 a6, Black gains queenside space and prepares the freeing ...c5 break.
White builds the center with 9.e4, and Black strikes at d4 with 9...c5. After 10.e5 cxd4 11.Nxb5 axb5 12.exf6 gxf6, Black is a pawn up, but the kingside pawns are broken. After 13.O-O Qb6 14.Qe2 Bb7, the queen defends b5 and supports d4, and the bishop takes the long diagonal toward the open center.
The closed lines and other White ideas
15.c5, the pawn on c5 supports the bishop on d6, deep in Black's camp.The White course also covers Black's sharpest answers to 5.g3. Against 10...Be7, White goes after the dark squares with 11.Qh5 and 12.Qh6. Against the immediate 6...b5, White jumps to e5 with 7.Ne5 and breaks open the queenside with 9.b3.
When Black keeps the center closed with ...Nbd7 and ...Bd6, White reroutes the knight with 8.Nd2 and prepares e4. Against 8...b6, White breaks with 9.e4, puts a knight on d6 with 13.Nd6, and fixes the bishop there with 15.c5. Other lines show how to use the bishop pair after 9...Bxc3, how to open the center with 13.d5 against 8...Qe7, and how to punish 10...Bxc3 after an early 8...e5.
Black's answers to the Anti-Meran, the Moscow, and 5.g3
10...Bg7, Black has the bishop pair and a solid kingside, and ...e5 is the next goal.Against the Anti-Meran 6.Qc2, Black develops with 6...Bd6 and castles, then frees the position with the central break 8...e5 or with ...b6 and 14...c5. Against the Shabalov Attack 7.g4, Black takes the pawn with 7...Nxg4, attacks f3 with 8.Rg1 Qf6, and after 9.Rxg4 Qxf3 10.Rxg7 brings the other knight back with 10...Nf6. Against 7.b3, Black lines up a rook against the queen on c2 with 10...Rc8.
Against 5.Bg5, Black asks the question with 5...h6. After 6.Bxf6 Qxf6, the Moscow Variation, Black keeps the bishop pair and either fianchettoes with ...g6 and 10...Bg7 or strikes with 12...c5 when White builds an e4 center. After 6.Bh4 dxc4, Black holds the extra pawn with ...g5 and ...b5, and punishes 7.a4 with 10...Qxb2. The course also covers 5.g3, 5.Qd3, 5.cxd5, and 5.Bf4.
What to train first
Pick the course for the color you play.
- If you face the Semi-Slav Defense as White, start with the Semi-Slav Defense course for White. Learn the Ng5 and Nxe6 sample line first, then the closed lines with
8.Nd2. - If you play the Semi-Slav Defense as Black, start with the Semi-Slav Defense course for Black. Learn the Meran sample line first, then the answers to
6.Qc2and5.Bg5. - Whichever side you play, watch the bishop on c8 and the c4 square. Black needs ...dxc4, ...c5, or ...e5 to free the bishop, and White wants to punish the time Black spends on c4.
The Semi-Slav Defense gives Black a solid center with sharp counterplay and gives White many ways to fight for the initiative. Train the lines until you know when to win back the c4 pawn and when the initiative is worth more.