Category - Closed Game
Opening Move Sequence - 1 d4 d5, 2 c4 c6
ECO Codes - D10 to D17
In the early twentieth century, many master chess players from Slavic countries studied and analyzed this opening giving Slav Defense its name. However, it was mentioned as early as sixteenth century. It is now a well developed line in Queen's Gambit. Even though it is technically considered a Queen's Gambit Declined opening, it is now normally studied separately because it has so many in-depth variations.
Slav Defense is popular in tournament play and has appeared in recent world championship matches.
Slav Defense falls under the category of Closed Game openings that begin with 1 d4 d5. Its ECO codes range from D10 to D17.
Moves and Variations
1 d4 d5
2 c4 c6
While this is the normal sequence in Slav defense it must be remembered that positions in Slav can be achieved through other sequences; for instance by 1 d4 d5, 2 Nf3 Nf6, 3 c4 c6, or 1 Nf3 d5, 2 c4 c6, 3 d4 Nf6.
Slav defense redresses several problems faced by Black in Queen's Gambit Declined or QGD openings. In other variations of QGD move e6 is played hampering the development of Bishop at c8, here e7 pawn remains in place. This also helps against possible White Bg5 pin against Knight developed to f6. Slav defense also has a better pawn skeleton for Black and prevents the likelihood of an attack by White pawns on the Q-side.
Move c6 also allows Black an opportunity to keep the gambit pawn after dxc4, or to gain time by attacking the White piece that recaptured it, through the move b5 which is defended by pawn on c6.
On the down side, it must be remembered that the Bishop on c8 can only be developed after dxc4 and allowing White to control center, and after its development Black's Q-side will be weaker.
There are huge numbers of playable variations in Slav. We will only glance at them here.
Slav Exchange Variation which arises after 3 cxd5 cxd5 generally leads to draws with its symmetrical play with limited opportunities for both players. One of the reasons why Black prefers 2 ... e6 and then 3 ... c6 to enter Semi Slav Defense is a desire to avoid this variation.
Semi Slav Defense can be entered by playing ... e6 as 3rd or 4th moves here, as well as by other move orders starting 2 ... e6. Semi Slave is a well developed opening with extensive variations, so should be studied separately.
In case of 3 Nc3, Black cannot play Bf5 as third move since 4 cxd5 cxd5, 5.Qb3 will lose a pawn. Black also loses after 3 ... Nf6, 4 e3 Bf5, 5 cxd5 cxd5, 6 Qb3 Bc8, since subsequent White moves f4, Nf3, and Ne5, will give Black a huge disadvantage. So after 3 Nc3 Black can play Winawer Counter Gambit by moving 3 ... e5.
However, usually White will play 3 Nf3 and try to make the best of Black Bishop's absence in Q-side. The play may proceed; 3 ... Nf6, 4 e3 (Slav Declined) or 4 ... Bf5 5.cxd5 cxd5.
The path mostly taken is 3 ... Nf6, answered by 4 Nc3. Now Black has several responses.
4 ... Bf5 is not advantageous for Black because after 5 Qb3 or 5 cxd5 and 6 Qb3 White will benefit. 4 ...e6 as usual will transform to Semi Slav Defense. The other available moves are 4 ... dxc4, and recently developed 4 ... a6.
4 ... dxc4 is called Slav Accepted. A combative White can reply with 5 e4 b5 (Slav Gambit). Play may continue to Geller-Tolush Gambit (6 e5 Nd5, 7.a4 e6). These lines of play are still in development. Analysts have questioned whether the gambits are worth the attack gained by White and are inclined favor the opinion that this will favor Black. Other possibilities for White are more calm Alekhine Variation (5 e3) and combative Alapin Variation (5 a4 with 6 e4 and 7 Bxc4).
In response to Alapin, Black can play 5 ... a6 which can transform to Meran Variation in Semi Slav defense. Or Black can play Smyslov Variation (5 ... Na6) aiming after 6 e4 Bg4, 7 Bxc4 e6, 8 0-0 Nb4 for an attack using Knight move to b4. However, the main variation is 5 ... Bf5 (Czech Variation), which blocks 6 e4. After 6 e3 the play is called Dutch Variation and will continue calmly after 6 ... e6, 7 Bxc4 Bb4, 8 0-0 0-0. White can select Krause Attack (6 Ne5) to avoid that. By that move White aims for g3, and Bg2. Black can continue with 6 ... Nbd7, 7 Nxc4 Qc7, or with 6 ... e6, 7 f3 Bb4. In the second case play may proceed; 8 e4 Bxe4, 9 fxe4 Nxe4, 10 Bd2 Qxd4, 11 Nxe4 Qxe4+, 12 Qe2 Bxd2+, 13 Kxd2 Qd5+, 14 Kc2 Na6.
In another response to Alapin, Black may play 5 ... Bg4 and block 6 e4 by possibility of 6 ... e5. Here play may continue; 6 Ne5 Bh5.
