Although I don't doubt that James Rodriguez is very talented player, it's often overlooked that Samir Nasri was a genuine phenomenon when he broke into the Marseille first team as a teenager and maintained that reputation until he joined Arsenal.
I thought he struggled for a while to adjust at Arsenal, although he wasn't exactly bad either and still only the age Sterling is now. After that he was unstoppable.
Since joining us, he's been one of the most misused players I've ever seen. If he's given a central role and he can ever be arsed to challenge himself again, he'll go back to being that phenomenon.
Maybe that will be for us, maybe it won't.