French Defense: Winawer Variation, Advance Variation, Smyslov Variation

The French Defense: Winawer Variation, Advance Variation, Smyslov Variation is a chess opening classified under ECO code C19 in the Open Games & French Defense family, beginning with 1.e4 e5 or 1.e4 e6, including the Italian Game, Ruy Lopez, and French Defense. It is reached after 7 moves: 1. e4 e6 2. d4 d5 3. Nc3 Bb4 4. e5 Ne7 5. a3 Bxc3+ 6. bxc3 c5 7. a4. The resulting position leaves black to move.