PHILADELPHIA - With Jeremy Maclin out for the season and Riley Cooper undergoing counseling, the Eagles are looking for one or two wide receivers to step up and join DeSean Jackson and Jason Avant in the rotation.

"That's why we're here," new wide receiver Arrelious Benn said Sunday. "This is definitely an opportunity for us. You have to have that 'next-guy' mentality. When one guy goes down, the next guy has to be ready."

Benn's sore left knee prevented him from taking that step until Sunday. He hurt it during the team's first practice of training camp on July 26 and missed six practices before participating in Sunday's two-hour workout at the NovaCare Complex.

Now his challenge is to stay on the field.

The Eagles thought enough of his potential to acquire him in a trade with Tampa Bay on March 15 and then sign him to a one-year contract extension that runs through the 2014 season. The 6-foot-2, 220-pounder was the Buccaneers' second-round draft pick in 2010 but played in just 37 of a possible 48 games over three seasons because of injuries.

The 24-year-old had just four receptions for 26 yards and no touchdowns in eight games last season before being placed on injured reserve with his second knee injury in three years.

"The main thing for me is, I have to prove I can stay healthy," Benn said. "That's my main goal right now. If I can stay healthy, everything else will play out."

He's near the bottom of the unofficial depth chart. Benn, who also is a talented kickoff returner, got a chance to catch a few passes from veteran quarterback Michael Vick but mostly worked with rookie Matt Barkley and fourth-stringer Dennis Dixon.

"I was actually pleasantly surprised because of the time away," Kelly said of Benn's performance. "Sometimes there is an ease-back-in factor, and I didn't see that from him today. I've obviously got to look at the film, but I thought he looked pretty good. I expected some rust, to be honest with you, but he kind of flashed a little bit.

"I'm really happy that we had a chance to get him back out there today. He's a big, physical target and with his ability to also play special teams, he can bring a lot to the table."

He's got some catching up to do, however.

Second-year veteran Damaris Johnson is working in Cooper's spot as the starter with Jackson and Avant, who lines up in the slot. Undrafted rookies Ifeanyi Momah and Russell Shepard III have been impressive in the early going, as has Greg Salas.

All the receivers are starting to play better as they get more comfortable with Kelly's offensive system.

"I thought Damaris had a good practice today because he's starting to pick things up to the point where he's not out there thinking," Kelly said. "He's just reacting and going.

"It doesn't matter what position you play. Guys may seem like they're getting faster, but they're just running up to their potential because they don't have to think anymore. They know what they have to do and they execute it."

Contact David Weinberg:

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