Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bb5/3...f5/4. Nc3/4...fxe4/5. Nxe4/5...Nf6/6. Nxf6/6...Qxf6

Having avoided committing the queen to e2 on move 6, White typically puts it there anyway with 7. Qe2. This restricts Black's options, because now ...d5 would self-pin the c6-knight allowing White to capture the e5-pawn for zero compensation.

Viktor Kupreichik mixed things up a couple times with 7. O-O. If Black reacts the same way she would after 7. Qe2, with 7...Be7, White has a huge positive score with the plan of Bxc6 and Qe1. But alert Black players found 7...Nd4! to take advantage of the fact that the e-pawn isn't under any pressure.