1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1b5  3... g8f6  4. e1g1  4... f6e4  5. d2d4  5... e4d6  6. b5c6  6... d7c6  7. d4e5  7... d6f5  8. d1d8  8... e8d8  9. b1c3 Gukesh joins the team of elite players who are still trying to break the Berlin Defense by playing the endgame. If I'm not mistaken, this is the first time he's taken this path. 9... d8e8 Black needs to decide whether to bring the king to the kingside (the most solid plan) or to the queenside (the most ambitious plan). Firouzja chooses the former, but his games always go for wild complications sooner or later. 10. h2h3  10... f5e7  11. f1d1 The computer prefers to place the rook on e1, but this is certainly part of many hours of preparation by the Gukesh team, analyzing every detail to pose practical problems for Black. A possible explanation for the rook's choice of square is that after 11... e7g6  12. b2b3  12... f8e7  13. c1b2  13... h7h5 A typical plan in these positions, demonstrated in several games by Almasi and Kramnik, the two main precursors of the modern Berlin. This move serves several functions, both preventing the advance of the white pawn majority on the kingside, and preparing the activation of the rook after h4-Rh5. 14. d1e1 The rook returns to its most natural square. Oftentimes the play of an elite grandmaster is subtle enough to break classical rules, as in this case where the rook goes back and forth in the first few moves. 14... h5h4  15. c3e4  15... e8f8  16. a1d1  16... a8b8 Another very difficult and subtle move. I believe it's prophylaxis against the tactical idea of Nd6, when if the knight is captured White takes with a pawn and then pushes the pawn to d7. Now, with the b7-pawn protected, Black can simply move the bishop if White plays 17.Nd6. 17. e4f6 A totally surprising move. The knight is sacrificed on a square I didn't expect. 17... g6f4 Firouzja is up to the challenge. 18. f6d7  18... c8d7  19. d1d7  19... f8e8  20. d7d1  20... c6c5 An important move to prevent Nf3-d4. 21. f3d2  21... e8d7 The move of someone who is not afraid of anything, a faithful portrayal of Firouzja's playing style. Cautious chess players would never start this journey with the king. 22. d2c4  22... d7e6 The king has to be placed in front of White's rook, which gives rise to some tactical ideas. 23. d1d6 Gukesh sacs the exchange to start an attack. Who said the Berlin endgame was boring $2 23... c7d6  24. e5d6  24... e6d5 The only good square. 25. e1e5 White has other options, but none give an advantage.