Quiet Variation

The Quiet Variation, also called the Slow Slav, arises when White meets 3...Nf6 with 4. e3 instead of 4. Nc3. Because the queen's knight is not yet committed, the play is positional and flexible, and the game can branch into several structures. 4...e6 often transposes to a main-line Semi-Slav, although White can steer elsewhere with 5. Bd3, 5. b3, 5. Nbd2 or 5. Qc2 in place of 5. Nc3. Other tries such as 4...a6 and 4...g6 also appear regularly.

In the database the most frequent answer is 4...Bg4, the Pin Defense, followed by 4...e6 and 4...Bf5, the Schallopp Defense. In the Schallopp, 5. Nc3 e6 6. Nh4 gives White the bishop pair. In return Black's position stays sound, and the ...e5 break offers active chances. This line occurred several times in the 2006 World Championship. After 5. cxd5 cxd5 6. Qb3 White probes the queenside, which the bishop has left, but 6...Qc7 equalizes with accurate play. The Landau Variation, 6...Qc8 7. Bd2 e6 8. Na3, and the Amsterdam Variation, 5. cxd5 cxd5 6. Nc3 e6 7. Ne5 Nfd7, are named branches. Engines consider the position roughly balanced, and White's results resemble those of the main Slav lines.