1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. b1c3  3... d7d5  4. c4d5  4... e6d5  5. c1g5  5... c7c6  6. d1c2 The famous Carlsbad pawn structure has been reached, named after the current town Karlovy Vary in the Czech Republic. 6... h7h6 A modern treatment of the position. 7. g5h4  7... c8e6  8. e2e3  8... b8d7  9. f2f3 A flexible idea that can be attributed to Botvinnik. The great champion liked to play aggressively in the center in this system, rather than following the routine path of the minority attack. 9... f8d6  10. f1d3  10... c6c5 Tabatabaei modifies the pawn structure, using the drawback of the f2-f3 advance. Since the capture on c5 is not desirable for White at the moment (e3-pawn being exposed) So has to concede some queenside space to his opponent. 11. g1e2  11... c5c4  12. d3f5  12... e8g8  13. e1g1  13... d8e8  14. f5e6  14... f7e6 The first moment about which one can argue. The black king is getting exposed in the long run. Still, this is not yet relevant, at least for the foreseeable future. 15. a2a4 A novelty that intends to keep the black pawns separated. So hopes to swap his b-pawn for his opponent’s c4-one, thus exposing a potential weakness on the b-file. 15... a7a6  16. b2b3  16... a8c8  17. a1b1 For the time being, neither of the sides wants to make a concession and improve the opponent's rook. 17... d6b4  18. h4e1  18... d7b6  19. c2a2 The first major thought by So, who spent almost half an hour on his clock. It is indeed hard to suggest a more useful move than the one in the game. The queen simply side-steps the pin, protects the a4-pawn, and supports its further advance. 19... f8f7 A solid move that protects the b7-pawn and prepares the doubling of the rooks on the c-file. 20. b3c4  20... c8c4  21. a4a5  21... b4c3 And this is a serious inaccuracy. 22. e2c3  22... b6a4 And that completes the wrong plan. 23. c3a4  23... c4a4  24. a2d2 A very neat move $1 So protects the a5-pawn in advance and prepares the maneuver Be1-g3, after which his rooks would be soon doubled on the b-file and his whole strategy would triumph. 24... f7c7 Tabatabaei decided to sacrifice the ill pawn at once. 25. e1g3  25... c7c6  26. b1b7  26... e8g6 There is a typical burst of energy once one sacrifices a pawn in Black's position, but this would not last for long. 27. b7c7 It is instructive how neat So is when repelling the opponent's initiative. 27... c6c7  28. g3c7  28... a4c4  29. f1c1  29... g6e8  30. c7g3  30... e8b5  31. c1c4  31... d5c4  32. e3e4  32... b5b3  33. g3e1 The initiative is gone, the extra pawn remains, and the frustrated Tabatabaei quickly collapses under the pressure. 33... f6e8  34. d4d5 With the activation of the white queen, all of Black's hopes quickly fade away. 34... e6d5  35. d2d5 