Coming into this camp, it was pretty clear Polk would be fighting for a roster spot, the Eagles having signed Cowboys veteran Felix Jones late in the offseason. LeSean McCoy is going to be the starter (though McCoy currently is day-to-day after suffering what the Eagles said was a minor knee injury in yesterday's practice at Lincoln Financial Field). Bryce Brown probably makes the roster off gaining 347 yards last season in his first two starts. (Not that Brown isn't doing well in camp, but he'd have to look awful for the Eagles to give up on his potential.) Of course, given the frantic Kelly offensive pace, the Eagles could wind up keeping four running backs, but that's far from a given. There's a good chance either Polk or Jones doesn't make the team.
When the Eagles finally released a depth chart yesterday, McCoy, Brown and Polk were 1-2-3, with Jones tied with undrafted rookie Matthew Tucker for fourth string.
"Any running back we have in the room is threatening," Polk said after yesterday's workout, witnessed by what the Eagles said was a crowd of just under 20,000 fans. "I knew [Jones] was going to come in here with the same attitude as me, which was to make us better. We're closely knit; there's only five running backs. I believe we're the closest group on the team. Even if we're not in meetings, we're all together, hanging out, laughing."
Last year in Reid's system, the Eagles saw Polk as a guy they could slide over to fullback if need be. He says he carried about 230 pounds on his 5-11 frame, though Polk never looked all that chunky. Kelly doesn't use a fullback, and Polk astutely inferred the new coach's up-tempo offense probably wasn't going to need any 230-pound runners. So he lost 15 pounds.
"It was very hard," Polk said. "I love food. I love to eat. You've got to stay disciplined."
He said he hasn't been this light since his days at East Valley High School in Redlands, Calif.
Kelly's offense, Polk said, "demands a lot from the running backs, whether it's running the ball, seeing a hole, hitting it, catching the ball, running routes, going out to wideout . . . plus, we can run the ball six times in less than a minute. Just to be in shape, just to have that extra step, that extra breath of fresh air into your lungs, can go a long way.
"I feel way faster, especially coming in and out of my cuts, being able to run away, pick up the legs, just lateral movement, I feel way better."
Kelly said last week that Polk, "really, truly understands the blocking scheme, so he's patient in terms of understanding letting the blocks develop, but when he sees them, then sticking his foot in the ground and taking off. I think the last couple of days he's really come across."
When there's a coaching change, some guys' stock rises, other guys were better off under the old regime. It probably helped Polk that Kelly, the former Oregon coach, knew Polk as Washington's focal point, not just as an undrafted running back who didn't get any carries as a rookie.
"He was a workhorse for Washington. He was really the guy you had to stop," Kelly recalled. "But he has versatility and can catch a ball coming out of the backfield. I think he's not just a one-dimensional guy, either."
Polk said he was mostly a receiver in high school, only played running back 1 year. He said he feels comfortable lined up in the slot, where Kelly has put him several times thus far.
Polk said he's good friends with former Oregon backs LaMichael James, now of the 49ers, and Kenjon Barner, now of the Panthers. He said he always liked the versatile way Oregon used its backs.
"They were next to perfection," Polk said. "I just wanted to show I could be that back, to get it done, whatever he asked of me."
Polk knows he'll have to perform well on special teams, starting with this Friday's preseason opener against the Patriots, to ensure his roster spot. That's an advantage he should have on Jones - the former Dallas first-rounder isn't going to be an asset covering punts or kickoffs (though he could return kickoffs).
"The best thing I can do is try not to get caught up in the numbers game," Polk said, "just steadily try to improve."
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