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Dion Lewis is a good young running back prospect who would make about every NFL roster as a second or third string running back.
The problem Lewis faces this summer is the amount of unknown competition he will go up against.
Bryce Brown, the Eagles' recent seventh-round draft pick and Chris Polk, an undrafted free agent, will both be competing with Lewis for the final two running back spots on the roster, behind LeSean McCoy.
One of those three players will be cut.
Which player it will be is a mystery right now. Either of these three backs could get the boot.
Lewis isn't a big back. He is one of the shortest backs in the NFL at 5'8". He still has a great deal of lower body strength and quick feet.
He has the ability to be a really good player. He hasn't shown a lot of ability as a receiver or in pass protection.
Coaching can fix that, especially in his first full offseason in the NFL.
Brown and Polk have the talent to be first or second round draft picks, but they also have issues that kept them out of the first two days of the draft. They kept Polk out of the draft altogether.
Brown is comparable talent-wise to Adrian Peterson, but his commitment to football has been comparable to Maurice Clarett or JaMarcus Russell.
NFL teams had enough concerns about Polk's durability to not draft him last April.
That has to mean something. He gets to prove that he is healthy this summer.
Outside of Trent Richardson, Polk might be the most versatile back in the draft when healthy. He is a big back who catches the ball out of the backfield with ease. He had over 1,800 total yards this past season at Washington.
It's a matter of potential versus reality this summer at running back.
The Eagles have a good idea of what they have with Dion Lewis and what he could turn in to.
Polk and Brown are the mysteries, as they are both wild cards in camp.
They could be spectacular or they could be just so-so.