1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. b1c3  3... f8b4  4. g1f3  4... d7d5  5. c1g5  5... h7h6  6. g5h4  6... d5c4  7. a2a3  7... b4c3  8. b2c3  8... b8d7  9. e2e3  9... b7b5  10. a3a4  10... c7c6  11. d1b1  11... d8a5 Navara deviates first  from a game that Mamedyarov lost recently in the Netherlands. 12. b1b2  12... f6e4  13. a4b5  13... a5b5  14. b2c1  14... c6c5  15. f1e2 For the pawn White has solid compensation thanks to  the bishop pair and the better pawn structure. 15... e8g8  16. e1g1  16... c8b7  17. a1b1  17... b5c6  18. e2c4  18... c5d4  19. c4b5  19... c6c7  20. c3d4  20... f8c8  21. c1b2 With the strong center Mamedyarov definitely wants  to keep the queens. The chances for a kingside attack he might get are  quite serious. 21... d7b6  22. f1c1  22... c7d6  23. f3e5  23... g7g5 A good practical  chance. Black swaps off the dangerous bishop. 24. f2f3 "This was a mistake as I am all of a sudden fine now." (Navara) 24... g5h4  25. f3e4  25... b7e4  26. b2f2 The point behind Mamedyarov's play.  26... d6e7  27. b1a1 This is inaccurate. 27... c8c1  28. a1c1  28... b6d5  29. b5d3  29... e4d3  30. e5d3  30... e7f6 Navara covered his king and kept the extra  pawn. Now Mamedyarov needed to find the most precise path to the draw. 31. f2f6 But he could not. 31... d5f6  32. g1f2  32... a7a5  33. c1a1  33... a5a4  34. a1a3  34... f6e4 An additional possibility in comparison to the line from above. 35. f2e1  35... a8b8  36. d3c5 White needs to get rid of the knights if he wants to have any chances of survival. 36... b8b1  37. e1e2  37... b1b2  38. e2d3 A curious position. It seems as Black  is completely winning, but Mamedyarov always has some counterplay. 38... e4f6  39. a3a4  39... b2g2  40. d4d5 Again this move! 40... g2g5  41. c5e4 Once more White searches for a knight swap. 41... g5d5  42. d3e2  42... f6e4  43. a4e4 So, Navara managed to increase his material advantage. However,  he is facing two serious problems in the rook endgame. First, the h-passer is doubled. Second, he often has to avoid the possible endgame with two  extra f- and h-pawns for Black as it is as a rule a draw. (True, Kramnik  once won it against Aronian, but that is another story.) 43... h4h3  44. e4h4  44... g8g7  45. h4h3  45... g7g6  46. h3h4 Activating the rook at once: 46... d5h5  47. h4g4  47... h5g5  48. g4h4  48... g5f5  49. h4g4  49... g6h5  50. g4a4  50... h5g5  51. a4b4  51... g5g6  52. b4g4  52... f5g5  53. g4h4  53... g5h5  54. h4g4  54... g6f6  55. g4f4  55... f6e7  56. h2h4 Mamedyarov stabilized the position but still has to  prove the draw. 56... h5e5  57. f4a4  57... f7f5  58. e2f3  58... e7f6  59. a4b4  59... f6g6  60. f3f4  60... e5a5  61. f4f3  61... g6h5  62. e3e4 Forcing more exchanges. The general  defensive principle in such situations is to trade pawns.