And this is the decisive mistake.
1. e2e4  1... c7c5  2. g1f3  2... b8c6  3. b1c3 In a must-win situation, Carlsen follows the  advice of Sveshnikov and rejects the main lines. 3... e7e5  4. f1c4  4... f8e7  5. d2d3  5... g8f6  6. e1g1  6... e8g8  7. c3d5  7... d7d6  8. c2c3 It is effectively a Ruy Lopez/Italian  now. 8... a8b8  9. a2a4  9... f6d5  10. c4d5  10... e7f6 Radjabov frees the e7-spot for his knight. 11. f1e1  11... f8e8 A novelty. Apparently, the Azeri GM did not want to double  his pawns on the e-file. 12. c1d2 White's plan is clear: to expand on the queenside while the  opponent is busy dealing with his central bishop. 12... c6e7  13. d5c4  13... e7g6  14. b2b4  14... b7b6  15. b4b5 Carlsen wins the battle on the queenside. Next a4-a5 in the proper moment will help him open the game in his favor. 15... c8e6  16. c4e6  16... e8e6  17. c3c4  17... g6f4  18. d1b3  18... g7g5 The kingside is the only place where Radjabov can show some  activity. However, while pushing the pawns he weakens his light squares. 19. d2e3 With the idea to maneuver his knight to the f5outpost. 19... g5g4  20. f3d2  20... h7h5 Radjabov is trying to prevent that. 21. d2f1  21... h5h4 The g3-square is covered, but the knight can use another  route. 22. b3d1  22... f6g7  23. e3c1 Carlsen is consistent in his plan. The knight will make it to the f5-square, no matter what. 23... e6g6  24. f1e3  24... d8d7  25. e3f5 That is also good for an edge, though.  White is about to open the queenside and penetrate there, thus Radjabov  needs something creative, urgently. 25... g7f6  26. a4a5  26... g8h7  27. a5b6  27... a7b6  28. c1e3 White is ready to double along the a-file, and Radjabov seizes  his chance. 28... d6d5 The best practical try. 29. e3f4 Now it is getting messy. Carlsen's exchange is fully compensated, no doubt about it, but the major  black pieces start to work too. 29... e5f4  30. c4d5  30... f6a1  31. d1a1  31... b8e8  32. f5h4  32... g6g5  33. g2g3  33... f4f3  34. h2h3 It is essential to open air for the king. 34... g5h5  35. h4f5 But this is a mistake that almost lets Radjabov off the hook. 35... h5f5 Once more Black seizes his chance. 36. e4f5  36... e8e1  37. a1e1  37... d7d5  38. e1e7  38... d5f5  39. h3g4  39... f5d5  40. e7f6  40... h7g8 To set the queen free.  41. f6f5  41... d5b3  42. f5f3  42... b3b5  43. f3d5  43... b5e8 A step in the wrong direction. 44. g4g5 