1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1b5  3... g8f6  4. e1g1  4... f6e4  5. f1e1  5... e4d6  6. f3e5  6... f8e7  7. b5f1  7... c6e5  8. e1e5  8... e8g8  9. d2d4  9... e7f6  10. e5e1  10... f8e8  11. c1f4  11... e8e1  12. d1e1  12... f6d4 A dangerous move, which is not the most popular. In exchange for the pawn White gets a superior pawn structure and it will be difficult for Black to finish development. Carlsen has some experience in this position, but all his previous opponents preferred the main move, 12...Ne8. The fact that Carlsen didn't win any of those games says a lot about the solidity of Black's position. 13. f4d6  13... c7d6  14. b1c3  14... d4c3 [%c_effect c3;square;c3;type;Inaccuracy;persistent;true] Black is in trouble now. 15. e1c3 The extra pawn doesn't count for Black—in fact it even hinders the development of the bishop. 15... b7b6  16. c3f3 [%c_effect f3;square;f3;type;GreatFind;persistent;true]