Eagles general manager Howie Roseman said that he could not estimate how long Cooper would be out until he had an X-ray and the team's medical staff evaluated the third-year receiver.
"I think it's a bump in the road," Roseman said. "He'll recover from it."
Cooper entered camp as the Eagles' likely fourth receiver. He filled that role most of last season and was also a special-teams standout. He did start three games when Jeremy Maclin was sidelined and finished the season with 16 catches for 315 yards and one touchdown.
"He's had a good offseason, and because he's had that offseason he's gotten a lot of reps . . . and gotten stronger and got more knowledge of our system, and that will benefit him when he's ready to come back," Roseman said.
When asked if the Eagles would consider signing a free-agent receiver in light of Cooper's injury, Roseman pointed out that he had 12 other receivers on the roster. The similarly sized Marvin McNutt could get additional opportunities to impress coaches. He's made several nice catches at Lehigh University, although he isn't particularly quick off the line.
Cooper (6-foot-3, 222 pounds) and McNutt (6-2, 216) are the two biggest receivers in camp. Several free agent receivers who are still on the market could help the Eagles in the size department. Braylon Edwards (6-3, 214), Mike Williams (6-5, 235), and Plaxico Burress (6-5, 232) remained unsigned - perhaps for good reason.
The Eagles flirted with the idea of bringing Burress, 34, aboard after his release from prison last year. He has lobbied hard for Andy Reid to bring him to Philly, but his best days are certainly behind him.
"We bring competition and depth at every position, because this is a game where there's going to be some attrition," Roseman said. "We're excited about the guys on our roster. At any position, if there's something that interests us, we'll explore it."
The Eagles typically need their fourth receiver to help out on special teams on game days. Aside from McNutt, the Eagles have other receivers in camp vying for a roster spot, although none anywhere as big.
Chad Hall has the most experience, having played in 15 games for the Eagles over the last two seasons. Mardy Gilyard played in 11 games for the Rams in 2010. Ron Johnson and Jamel Hamler spent part of last season on the Eagles' practice squad. Tiger Jones played four seasons of Arena League football. Damaris Johnson, Elvis Akpla, and McKay Jacobson are undrafted rookies.
The 5-foot-8 Johnson is perhaps the most appealing of the seven. Reid said Friday that Johnson has the early edge as the team's punt returner. He stood out during Saturday's practice when he took an end-around in team drills and scooted 30-plus yards, unfurling a variety of nifty moves.
Cooper went down long before the Eagles started hitting. He injured his collarbone when he fell awkwardly after getting tangled up with cornerback Curtis Marsh during one-on-one drills. He lay on the ground for several moments before he walked to the trainers' tent and was eventually carted off the field.
He wasn't the only injury of the day: Starting defensive end Jason Babin strained his right calf, and defensive tackle Antonio Dixon left practice early with cramps.
Contact Jeff McLane at 215-854-4745 or firstname.lastname@example.org, or follow on Twitter @Jeff_McLane.