The knight returns so that Black can prepare c6-d5. A very difficult move for someone not familiar with this opening, but Nakamura has this very well studied.
1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1c4  3... g8f6  4. d2d3  4... h7h6 A flexible move that keeps several plans open: he can play g7-g5 and Bg7, a bold idea that became popular a few years ago; or play g6-Bg7; or simply develop the bishop on its natural square, c5, without White being able to play Bc1-g5. 5. c2c3  5... f8c5  6. b2b4  6... c5e7  7. a2a4  7... d7d6  8. d1b3  8... e8g8  9. e1g1 