context: 1. d2d4  1... d7d5  2. c2c4  2... e7e6  3. b1c3  3... c7c6  4. e2e4 A sharp variation that is known as the \"Marshall Gambit.\" Considering that there's another gambit with the same name that is considered one of the best options for Black against the Ruy Lopez, it's safe to say that Frank really knew how to sac a pawn in the opening. 4... d5e4  5. c3e4  5... f8b4  6. c1d2 This is where the gambit really starts. A move like 6.Nc3 keeps material equal, but it's much less fun. 6... d8d4 