1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1c4  3... g8f6  4. f3g5  4... d7d5  5. e4d5  5... c6a5  6. c4b5  6... c7c6  7. d5c6  7... b7c6  8. b5d3 \"It's just sometimes fun to pull these old variations out\" (Nakamura) Whatever works should not be fixed. A few years back, Nakamura picked up this line to win the most important final game at the USA championship. 8... f6d5  9. g5f3  9... f8d6  10. e1g1  10... d5f4 \"This did not completely surprise me\" (Nakamura). 11. b1c3  11... f4d3  12. c2d3  12... e8g8  13. b2b3  13... f8e8  14. f1e1  14... c6c5  15. c1a3  15... a5c6  16. c3e4  16... d6f8  17. a1c1 [#] 17... f7f5 Caruana might have messep up something when memorizing his line. 18. e4c5  18... d8d5  19. d1c2 Simple and effective. White is simply up two pawns. There is not enough compensation. 19... e8d8  20. c2c4  20... d5c4  21. c1c4 White's pawn remain ugly, but are extra. 21... d8d5  22. e1c1 