Trendsetter Gopal Menon plays the fashionable 4...Qb6!? (I don't even know the name of this line: 2...Nc6 and 4...Qb6 is the Grivas Sicilian proper, and the Grivas is reached in the game by transposition.)
25...Qb3?! 26.Rda1! did not work well for Black in the game. Instead, Black could have played 25...Bxc4! 26.Qxc4 Rxa5, the point being that the pawn fork 27.b4 can be met by 27...Ra4 with messy play.