He showed what he could do in the open field with some big gains, but IMO Sproles also did well running between the tackles. He was getting ~3 yards on plays without much of a hole there. From what I remember last time I watched him (previous preseasons), he got stoned for no gain or a loss on similar plays. Sproles also did a solid job handling kicks and punts, which is probably going to be his primary role there. The way he played, he might earn some more PT on long yardage situations.
It was good to see this kind of performance from him, b/c I had read some SD newspaper people guessing that he might get cut this year.