The success of the 2015 Eagles hinges on, in large part, how several key players bounce back from injury.

Sam Bradford didn't take snaps during the Birds' full-team drills at OTAs Monday, but he did participate in seven-on-seven drills, at one point flashing his arm strength and accuracy hitting Zach Ertz deep downfield. He is getting better each week, but he is still not 100 percent.

"My body is trying to adjust back to game speed," the former Ram, swapped for Nick Foles this March, said. "There is only so much you can do when throwing routes on air, but when you're out there actually ruining plays it forces you to up the tempo."

Bradford, who watched Mark Sanchez get the reps with the Eagles' first team offense, says his doctors are allowing him to increase his workload by 10-to-15 percent each week, a trend they will continue.

But even in a limited capacity, Bradford is impressing his teammates.

"The accuracy I have seen so far, it's looking good," linebacker Brandon Graham said. "I am excited for him to be in there 24-7 with nothing else holding him back because we are going to need him this year."

Bradford tore his ACL in Week 3 against the Browns last season, putting him a few months behind the recovery of another new Eagle, teammate Kiko Alonso. But both are making plays on the practice field, knee injury or no.

"That knee stuff is serious, but it's all in your head too," Graham said. "When it finally heals it's about what your where your mentality is."

Starting at linebacker alongside Graham will be Alonso, who injured his knee during the 2014 offseason. He's close to 100 percent, or if you ask Graham, he might be at 110 percent.

"I think Kiko is going to bee a guy you will see around the ball all the time," Graham said. "That guy doesn't get tired. You wouldn't even think he had a knee injury the way he's moving right now."

Alonso is part of a deep and talented linebacking corps, headlined by DeMeco Ryans and Mychal Kendricks. It's a group that challenges Alonso and helps him to improve even further (he led all rookies in tackles in 2013 with 159).

"It's always great to work with guys of that caliber," Alonso said. "Watching those guys, how they work and how they play, it really helps."

Alonso and Bradford are fighting a few more obstacles than your average NFL player this offseason, and each hopes his on-field play helps earn the respect and admiration of teammates and coaches.

"It is a little bit difficult," Bradford said. "I wish I were out there taking every rep, it would make it a little easier to take on that leadership role and develop some of those relationships but theres other ways to do that, pull guys aside after practice or in the weight room... I have been trying to develop relationships and I think that's what it's all about."