PHILADELPHIA (973espn.com) - Jim Schwartz compared Brandon Graham to a caged-up lion let loose when he returned to the practice field last week.

The Super Bowl hero had been unable to do anything since undergoing angle surgery stemming from an injury suffered on Christmas night last year, something the veteran defensive end pushed through in a postseason that culminated with the strip sack of Tom Brady which essentially clinched the first Super Bowl win in Eagles history.

Already famous for his effusive energy Graham was a welcome sight for a defensive line Schwartz calls the engine of his defense.

"He was like a caged-up lion or something," the DC said when discussing Graham's return. "He just had so much energy out there yesterday (Sunday)."

"He just knows that I love to play football," Graham said when told about Schwartz's description. "It's pretty cool. ...I know exactly what he means. Yesterday, I was excited. I was out there, talking, being me."

Graham, though, admitted he's not 100 percent just yet and has stressed he needs to up his conditioning before the old 55 is wreaking havoc again on opposing offensive lines.

"I'm feeling good," Graham said. "[Sunday] was really good. Good start. It let me know I'm not that far. I wasn't out of shape. That was pretty cool to know all the hard work we've been doing this offseason in the training room and the weight room has been worth it because now on the field, I ran a couple plays and I wasn't as tired."

Graham labeled himself at 80 percent, 10 days before the season opener against the Atlanta Falcons and Schwartz is interested in seeing how Graham responds from day to day now that he is back at practice.

"How he responds coming back on a day, coming back on two days, what the trainers think, what the doctors think," Schwartz explained. "And then with us, how we think he can perform, all of that will go into what it looks like: whether he's going to play; whether he's not; the number of plays; all that will be determined over the course of the next 11 (or so) days."

The Eagles are very deep at defensive end with Chris Long, Derek Barnett and Michael Bennett all available and ready to go. In the preseason, Long and Bennett have spent most of their time at left end, Graham's usual spot, with Barnett at right end. In the team's Nascar package Bennett moves inside next to Fletcher Cox.

Last season that was Graham's role as he started at left end and moved inside on obvious passing downs. Bennett, who came over in a trade with Seattle, offers similar versatility as the veteran Pro Bowl selection can play inside or outside.

In some ways, it's an embarrassment of riches for Schwartz.

"We expect a lot from our defensive linemen in general," Schwartz explained. "... We rotate players up front and we expect them to come in and give us a lot of energy. We expect them to be able to win in pass-rush without blitzing and penetrate and make things happen against the run.

"Brandon does all of those things. He’s a real important guy, but there's a difference having his energy on the field. It was good to have that back. Even though it wasn't very much yesterday, it was good having that back on the field. We look forward to more of it."

-John McMullen covers the Eagles and the NFL for 973espn.com. You can reach him at jmcmullen44@gmail.com or on Twitter @JFMcMullen