context: 1. e2e4  1... e7e5 Sarana is known as a fierce Najdorf player, but I suppose he decided to prepare a more solid defense against such strong opponents. For the spectators it's always a pity when the Najdorf gets replaced by something else. 2. g1f3  2... b8c6  3. f1c4  3... g8f6  4. d2d3  4... f8e7  5. e1g1  5... e8g8  6. b1c3  6... d7d6  7. a2a4  7... a7a5 A modern move, stopping the advance of White's a-pawn. This plan has been tried by some very strong players, including Carlsen and Artemiev. 8. f1e1  8... c8e6  9. c3d5 Judging by the opening outcome of this game, this move is an excellent way to develop the initiative. 9... e6d5  10. e4d5  10... c6b4  11. d3d4 The only move to justify 9.Nd5. 11... e5e4  12. f3d2  12... c7c6 The best chance to fight for equality. 13. c2c3 A very accurate move. I suppose, from the time Tabatabaei spent to arrive at this position, that it was found over the board. 13... b4d5 A good reply. 14. d2e4  14... f6e4  15. e1e4  15... d5f6  16. e4e1  16... d6d5  17. c4d3 With the bishop pair, White has a slight advantage. This is as good as it gets when playing against 1.e4 e5. Give me this position for White any day and I'll be happy. 17... g7g6 A new and logical move, restricting the bishop on d3 and preparing …Re8-Bf8-g7. The problem is that it releases the h6-square for the dark-squared bishop. 18. g2g3 Giving the king some air. White has a long-term positional advantage (the bishop pair), so no rush is necessary. 18... f8e8  19. d1f3  19... e7f8 A natural move to exchange rooks and place the bishop on g7, but this is a clear mistake. 20. c1g5  20... e8e1  21. a1e1  21... f8g7 Adding more problems to Black's position. 22. f3f4 This is essentialy a winning move. White prevents Qd6, which is Black's only plan. It's curious that Sarana played very fast up to this point. Something went really wrong with his opening preparation. 22... a8c8  23. d3f1 Black is paralyzed as there's no way to get out of the pin. White can play h4 followed by Bh3 and reinforce the position as he pleases, so Sarana decides to sac a pawn in order to create some chances. 23... h7h6  24. g5h6  24... g7h6  25. f4h6  25... d8b6  26. f1h3  26... c8f8 The rook needs to go to this passive square in order to protect the kingside. 27. e1e6 White has several winning moves. 27... f6h7  28. e6e2  28... b6b3 Trying at least to attack the the a4-pawn, but the queen is far from the kingside and the absence is felt. 29. h6f4  29... b3a4  30. g1g2 A prophylactic move. 30... c6c5  31. h3g4 Good enough. The h-pawn is ready to move to h5, destroying the king's position. The bishop can go to f3, attacking the pawn on d5. 31... c5d4  32. h2h4 Much better than recapturing the pawn immediately. 32... a4c6  33. f4d4  33... f8d8  34. g4f3  34... b7b5 I guess this was played in order to prevent c3-c4 after ...Nf6. 35. e2e5  35... h7f6  36. h4h5 Destroying the king's protection. 36... d8d7  37. h5g6  37... f7g6  38. g3g4 The final attack begins. 38... g8f7  39. g4g5  39... f6e4  40. f3g4  40... d7e7 Black has to go for a hopeless endgame.