For any Pitt fans (or Eagles fans for that matter) hoping to see Dion Lewis back up Lesean McCoy in Philadelphia this season, that might not happen. A writer on the Eagles' official website weighs in on the issue and doesn't think Lewis will be the primary backup in his rookie year.
Bo Wulf from the Eagles' site had this to say:
Dion Lewis , McCoy's one-time replacement at the University of Pittsburgh, was drafted by the Eagles in the fifth round of last April's draft and profiles as a dynamic, albeit undersized, option out of the backfield who is surprisingly adept between the tackles. But the Eagles aren't likely to pin their entire hopes on the unproven rookie
Another site thinks it's not so much about Lewis being a rookie as it is about him being a similar type of back, even suggesting the Eagles trade Lewis for a bigger back.
Philadelphia could be a contender in the NFC to win the conference and it makes sense that they'd want another proven rusher behind Shady. But I'd be surprised to not see him in there as a third-down back on occasion - he has too much talent to not get on the field at all.