context: 1. d2d4  1... d7d5  2. c2c4  2... e7e6  3. b1c3  3... c7c6  4. e2e4 A sharp variation that is known as the \"Marshall Gambit.\" Considering that there's another gambit with the same name that is considered one of the best options for Black against the Ruy Lopez, it's safe to say that Frank really knew how to sac a pawn in the opening. 4... d5e4  5. c3e4  5... f8b4  6. c1d2 This is where the gambit really starts. A move like 6.Nc3 keeps material equal, but it's much less fun. 6... d8d4  7. d2b4  7... d4e4  8. g1e2  8... b8a6  9. b4f8 A pretty move that is well-known. 9... e4g6 Very rare. Arjun is an interesting player for the audience since he is always willing to take great risks in order to play for a win. He surely has a lot of analysis here. Both 10.Qd6 and 10.Nf4 are critical. 10. f8d6 Already an opening novelty. Robson was clearly surprised by the last move and spent a long time on his reply. 10... e6e5 Both 10...Ne7 and 10...Nh6 are good options. 11. d6e5  11... a6b4 This tempting move is a mistake. Black should choose either 11...Ne7 or 11...Nh6. 12. e2f4 The refutation of Black's play. Robson needs a lot of praise to find all this over the board, in a rapid game, with the pressure of being caught in the opening. 12... g6f5  13. d1d6 13.Bxg7 is also possible, but it's so hard for a human to evaluate that I prefer the move played in the game. 13... f7f6  14. e5c3  14... b4c2  15. e1d2  15... c2a1  16. f1d3  16... f5d7  17. h1e1 Robson starts to falter after magnificent play. He played so well up to this point that it almost feels unfair that he loses this game. But let's not forget to praise Arjun as well - he does this on purpose, knowing he is walking a tight rope, but he is confident in his ability to outcalculate his opponents. 17... e8f7  18. d6c5  18... g7g6 Arjun finds the best defense. 19. f4e6  19... d7e6  20. e1e6  20... c8e6 The position is still very dangerous for Black, but at least there's no mating attack.