Chess Opening Theory/1. e4/1...c5/2. Nf3/2...d6/3. d4/3...cxd4/4. Nxd4/4...Nf6/5. Nc3/5...e6/6. g4/6...h6

=Scheveningen Variation, Keres Attack= White's 6. g4 begins the Keres Attack, a sharp and important line in the Scheveningen Variation. Black's 6...h6 is the standard continuation, preventing an advance to g5 which would force the f6 knight to retreat.

Now White has a number of options. These include advancing anyway with g5 and exchanging pawns or continuing the pawn storm with h4, h3 or f3.