1. g1f3  1... d7d5 Duda was probably caught by surprise in the opening. It seemed so natural to expect 1.e4, which is Ian's main move. Also, Nepo has been playing the Petroff a lot with Black as of late, so he probably has some sense of where to put the most pressure. Duda's other option is the Najdorf, which Ian has crushed once already this tournament. I myself was also not expecting anything else on move 1, but the surprise clearly paid off. 2. g2g3  2... c8g4  3. f1g2  3... e7e6  4. e1g1  4... b8d7  5. h2h3  5... g4h5  6. d2d4  6... g8f6  7. c2c4  7... c7c6  8. c4d5  8... e6d5 All of this is reasonably well known and has been played a bunch of times before. I never fully trusted these positions for Black though. 9. f3e5 Bold, and I like it $1 9... d7e5 A human response, but not a great one. 10. d4e5  10... f6e4  11. b1d2  11... e4d2  12. c1d2 Already, Black's position is very difficult. I like White's kingside and central space, and the h5-bishop is going to get harassed once the pawns get moving. 12... f8c5  13. a1c1 The first new move of the game, and a good one. I have to imagine Nepo was prepared at least up to this point. 13... d8e7  14. g1h2  14... e8g8  15. g3g4  15... h5g6  16. f2f4 White is threatening f5, and Black has no good options. Duda found the least bad one. 16... h7h6  17. d1e1 Ian took a very long time on this move, which is not something he is known to do. The machine is not a fan, but I like it quite a lot. White has this nice and simple plan of bringing the queen to g3, and one could imagine b2-b4-b5 coming as well. 17... f8e8  18. e1g3  18... g6h7  19. h3h4 Simple and incredibly effective. White has a big kingside pawn mass, so put it in motion $1 The attack is coming and is very hard to stop. 19... a8d8  20. g4g5 So simple. Black is already in trouble and has to find an only move to not die immediately. 20... h6g5  21. h4g5  21... c5b4  22. d2b4  22... e7b4  23. f4f5 Of course the b2-pawn is of little consequence. 23... b4b2  24. e5e6 Not the most precise, but certainly good enough. 24... f7e6  25. g5g6 This seems a bit careless. 25... e6f5  26. g6h7  26... g8h8  27. c1b1 Now, since Black did not take the h7-pawn, he is unable to transition to an endgame with Qe5. 27... b2f6  28. b1b7  28... e8e2  29. f1f5 Not too difficult, but nice all the same. White's extra piece keeps his own king safe, while Black's is clearly done for with all the heavy pieces on an open board. 29... f6h6  30. h2g1 