Preventing  the trade.
1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1c4  3... f8c5  4. c2c3  4... g8f6  5. d2d3  5... d7d6  6. e1g1  6... h7h6  7. f1e1  7... e8g8  8. b1d2  8... a7a5 Nakamura is the main proponent of this line against the Italian.  He has had running mini-matches against Ding, Carlsen, and So. 9. d2f1  9... c8e6  10. c4b5  10... c5b6  11. f1g3  11... f6h7 A novelty. This idea is mostly seen in the lines where  the black bishop stands on e7. Here too, it is possible and aims to a  better control of the d4-square. 12. h2h3  12... h7g5  13. f3g5  13... h6g5  14. d3d4 So breaks through the center anyway. 14... e5d4  15. b5c6  15... b7c6  16. c3d4  16... c6c5 Black is trying to clarify the  central situation, but this leads to problems. 17. d4d5  17... e6d7  18. a2a4 An important move that keeps the black dark-squared  bishop locked. 18... f8e8  19. c1d2  19... c5c4 Nakamura is OK to sacrifice the pawn after all. 20. d1f3  20... a8b8  21. d2c3  21... b6c5 As the bishop really needs out.