Nimzo-Indian Defense: Sämisch Variation, Keres Variation

The Nimzo-Indian Defense: Sämisch Variation, Keres Variation is a chess opening classified under ECO code E25 in the Indian Defences family, where Black responds to 1.d4 with 1...Nf6, including the Nimzo-Indian, Queen's Indian, and King's Indian. It is reached after 8 moves: 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. f3 d5 5. a3 Bxc3+ 6. bxc3 c5 7. cxd5 Nxd5 8. dxc5. The resulting position leaves black to move.