In the common literature, it appears as truth that Karpov missed the winning a6! instead of Rxd1 on move 33, Game 41, in the first Karpov vs Kasparov match. But is the following position, derivate from above, really winning?

[Title "Black to move"]
[FEN "8/P3R1pk/7p/8/r4p2/1N5P/1b3PP1/6K1 b - - 3 46"]

If both sides make the best moves, it is a win for White or a draw?