Steiner Variation

The Steiner Variation, 1. e4 Nf6 2. e5 Nd5 3. c4 Nb6 4. b3, supports the c4-pawn with another pawn instead of reinforcing the center with 4. d4 or chasing the knight with 4. c5. Black usually strikes at e5 with 4...d6. The less common 4...e6 and 4...d5 are also seen, and White has done better against 4...d5. Engines judge the position roughly balanced, and Black scores slightly better in practice.