1. d2d4  1... g8f6  2. g1f3  2... b7b6  3. c2c4  3... c8b7  4. b1c3  4... e7e6  5. g2g3 This offers Black a choice  between the Queen's Indian and the Nimzo-Indian defenses. 5... f8b4  Kovalenko chooses the latter. 6. f1g2  6... b4c3  7. b2c3  7... e8g8  8. e1g1  8... f8e8 A change of heart. 9. f1e1 A useful move that prepares both e2-e4 and the maneuver Bg2-f1,  which would preserve the bishop pair. 9... d8c8  10. d1c2 Luring the bishop to e4 in order to win a tempo to attack it  later. 10... b7e4  11. c2b3  11... d7d6  12. g2f1 A typical maneuver. Now White wants to kick the bishop back with  Nf3-d2, followed by f2-f3 and e2-e4. 12... b8c6 It is time for Black to win tempos. 13. c1g5 Now that the  queenside knight cannot defend the other one, this makes sense. 13... c6a5  14. b3d1  14... f6d7 Kovalenko did not dare to accept the pawn. 15. f3d2  15... e4g6 This is not the right diagonal for the bishop. Its new  location only helps White develop the initiative here. 16. e2e4  16... f7f6  17. g5e3  17... c8b7  18. h2h4 Of course! Naiditsch has the strong center, and this naturally  associates with a kingside attack. 18... g6f7  19. d2b3  19... a5c6  20. d4d5 Now White firmly takes over the initiative. 20... c6e7  21. h4h5  21... e6e5 Alas, this does not bring the desired relief. 22. h5h6 Naiditsch hits where it hurts. The missing dark bishop makes  the defense of the f6-pawn impossible. 22... g7g5  23. f1h3 The same idea decides. Kovalenko cannot saveguard his kingside. 23... a8d8  24. d1f3  24... e7c8  25. h3d7  25... d8d7  26. f3f6  26... f7g6  27. f6g5 Two extra  pawns and an attack should easily be winning. 27... d7f7  28. f2f4  28... e5f4  29. g3f4  29... e8e4  30. e3d4  30... f7f5  31. g5g3  31... e4e7  32. d4e3 Ultimately Naiditsch decided to award the knight with the central outpost. 32... e7f7  33. b3d4  33... c8e7 Forced, and Kovalenko at least builds a  blockade. 34. d4f5  34... e7f5  35. g3g5  35... b7c8  36. e3d4  36... c8f8  37. e1e6 White is still  winning but has to be more careful than before. 37... f5d4  38. c3d4  38... f7f5  39. g5g3  39... f8h6  40. e6e8  40... g8g7  41. e8e7  41... g7h8  42. a1f1  42... g6h5  43. f1f2  43... h6f6  44. e7c7  44... h5g6  45. g3e3  45... f6h4 Now some unpleasant checks are always in the air. 46. f2h2  46... h4g4  47. h2g2  47... g4d1  48. g1f2  48... f5f8 However, the neat 49. c4c5 leaves  White in control as the opening of the long diagonal would be deadly for  the second player. 49... g6d3  50. g2g5  50... d1c2  51. f2g1 