Eagles still waiting on Chris Polk

PHILADELPHIA -- Chris Polk knows that nothing in the NFL is guaranteed, particularly for a player who went undrafted in 2012 and has 11 career carries in two seasons.

He also knows that Chip Kelly wants to see him on the field; the sooner the better.

Polk is entering his third season with the Philadelphia Eagles but he missed most of training camp and both of the team’s preseason games nursing a hamstring he injured early in camp. He did not practice this week and will not play against Pittsburgh on Thursday night.

“We can’t evaluate anybody if they’re not going to play in games or practice,” Kelly said on Tuesday when asked about Polk.

“He has a hamstring injury, so until he can go full, we’ll see. That’s all I get.

"A lot of that has to do with the pain that they feel. It’s not a bone where you can take an X-ray and say it’s 100 percent healed. ... It is a hamstring. For some guys, they respond a little quicker and other guys it takes a little while. It’s a tough thing with that injury.”

Polk said he would love to be practicing and will practice starting next week, whether or not he is 100 percent healthy. Polk said he tried to prove to coaches that he is committed during the offseason, when he was at the Eagles' practice facility at 6 a.m. working out and watching film.

Kelly would like Polk to be in the rotation with LeSean McCoy being the featured back and Darren Sproles in some hybrid role catching passes out of the backfield and giving McCoy a breather. But until Polk is on the field practicing, Kelly said it is hard to evaluate him.

Polk knows that his job is on the line.

“Yeah, there’s nothing guaranteed,” Polk said. “I wasn’t drafted. I’m not LeSean McCoy or Nick Foles. I’m not guaranteed anything, so I have to go out there and act like it’s my last day, and that’s why whether I’m practicing or sitting there watching, I’m always taking notes, watching everything because there’s always something you can get better at. You can be hurt, whatever, there’s always something extra you can do to get better and put your best foot forward on the field.”