Andy slipped a little bit after Cincy but I think he will bounce back.
he has to fix his serve.
Nishikori attacked his 2nd serve no less than 39 times in that match at Flushing Meadows.
you just cant allow that to happen if you are a top player and if you are nearly 6 foot 4.
If Mugray had a good serve (especially second serve) he would have many more slams.
But he's also a mental midget a lot of the time. And he doesn't have the mental stamina that it takes to get to number 1 and stay there like Federer, Nadal, and Djokovic have.
He'll still probably be number 1 someday just be default, when Djokovic fades out, since there is no one else on the horizon.