A bit timid.
1. e2e4  1... c7c5  2. g1f3  2... d7d6  3. d2d4  3... c5d4  4. f3d4  4... g8f6  5. b1c3  5... e7e5 Nakamura surprisingly repeats the risky experiment that guaranteed him a draw against Caruana in the Candidates Tournament—but did not yield a good position in the opening. 6. f1b5 [%c_effect b5;square;b5;type;GreatFind;persistent;true] 6... b8d7  7. d4f5  7... a7a6  8. b5e2 A new idea in this particular theoretical battle. 8... d7c5 The most natural square for the knight, although 8...Nb6 has also been played. 9. f5g3  9... b7b5 There are alternatives: