Sometimes when a player is physically gifted, which he is, they are slow to react because their pace/strength gets them out of trouble. You see it quite a lot.
He nearly got to Rodriguez in time which is some distance he quickly covered.
Even attacking he's slow to react in support. You can see his overlaps coming a mile off because he's 40 yards back before he starts to make his run. Credit to his oddly fast body because he does eventually get there just in time.
He's just too casual in how he plays and how he prepares himself. Part gets away with it because he is very gifted. If he had Gary Neville's temperamemt, what a player he'd be.