1. c2c4  1... e7e5  2. b1c3  2... g8f6  3. g1f3  3... b8c6  4. e2e4  4... f8c5 Black challenges his opponent on his own territory $1 5. f3e5  5... c6e5  6. d2d4  6... c5b4  7. d4e5  7... f6e4  8. d1f3  8... d7d5 [%c_effect d5;square;d5;type;Interesting;persistent;true] A fresh but risky line, according to the Azeri GM. 9. f1e2 The most reliable answer. White needs to complete his development ASAP. 9... d5d4 [%mdl 4][%c_effect d4;square;d4;type;Interesting;persistent;true] A promising side line. 10. f3e4  10... d4c3  11. e1g1  11... e8g8  12. a2a3  12... c3b2  13. c1b2  13... b4c5 This has been seen just once, and Caruana's next logical move turns out to be a novelty. 14. e2d3 There are no kingside defenders; therefore, this move is self-explanatory. 14... g7g6 A needed weakening, and White wants to capitalize on it at once. 15. e5e6 [%c_effect e6;square;e6;type;GreatFind;persistent;true] 15... d8e7 [%c_effect e7;square;e7;type;GreatFind;persistent;true] More or less the only move. 16. f1e1  16... a7a5 [%c_effect a5;square;a5;type;GreatFind;persistent;true] Solving the problem of the a8-rook. If it stays on its initial square, White would practically always have a decisive kingside superiority. 17. e4f4 Caruana prevents the activation of the black rook. At least for the time being. 17... f7f6 Solid play by Mamedyarov. Being a great attacker himself, he most likely did not even consider pawn-grabbing as an option. 18. d3e4 [%c_effect e4;square;e4;type;GreatFind;persistent;true] White is in time to force some concession. 18... a8a6  19. a1d1 But this does not look optimal. 19... a6d6 Black too could have been a tad trickier. 20. d1d6  20... c5d6 The problem of the black rook is solved; now the ball is in White's court. How to build the initiative $2 21. f4h4 No retreat $1 21... c7c6 Takes away the d5-square from the white bishop. Mamedyarov is ready to win the e6-pawn. 22. e4d3  22... d6a3  23. b2a3  23... e7a3 Mamedyarov has won a pawn but, what's more, has managed to trade another light piece. White needs strong threats, and he needs them now. 24. h4g3 The sacrifice on g6 is White's best hope. 24... f8e8 [%c_effect e8;square;e8;type;GreatFind;persistent;true] Played after a thorough thought. 25. d3g6 What else $2 25... e8e6 [%c_effect e6;square;e6;type;GreatFind;persistent;true] The nice tactical point behind Mamedyarov's idea $1 26. g6d3  26... g8h8  27. e1d1  27... a3d6 Black solidifies his position while keeping his extra pawn. Still, since his king is permanently weak, White keeps practical chances. 28. g3f3  28... d6e7  29. d3f1  29... e6e5 [%c_effect e5;square;e5;type;GreatFind;persistent;true] The ideal position for the rook; the black bishop is finally entering the game as well. 30. h2h4  30... c8e6  31. d1d4  31... e5e1 Very logical, as this move prevents the doubling of the white pieces along the d-file. But as we shall see, it allows Caruana another chance. 32. f3c3 [%c_effect c3;square;c3;type;GreatFind;persistent;true] The queen finds another way to pair with the rook. 32... e6g8  33. c3d2  33... e7e5  34. d4d8  34... e5a1 The culmination of the game. 35. d2d3 And a big miss by Caruana $1 35... a1b1 [%c_effect b1;square;b1;type;GreatFind;persistent;true] Now everything is covered, and the black king can escape the perpetual. 36. d8g8  36... h8g8  37. d3d8  37... g8g7  38. d8c7  38... g7g6  39. c7g3  39... g6f5 [%c_effect f5;square;f5;type;GreatFind;persistent;true] A bold move, and the king escapes. 40. g3h3  40... f5e5  41. h3g3  41... e5e6 