Eagles coach Chip Kelly identifies the gamble NFL teams have to make if they want to get franchise quarterback fast

Philadelphia Eagles coach Chip Kelly gutted his team this off-season in a roster overhaul that involved trading his starting quarterback Nick Foles to the St. Louis Rams for Sam Bradford, a player coming off of back-to-back ACL injuries.

While he drew plenty of criticism for the move, Kelly told Philadelphia Magazine's Tim McManus that he sees the trade as a calculated risk he needed to take, believing there are only two ways to get a franchise quarterback: draft one, or acquire one when he's coming off of an injury and his stock is low.

Since the Eagles had the No. 20 pick in this year's draft, they didn't have a shot at Florida State's Jameis Winston or Oregon's Marcus Mariota - the only two quarterbacks in the draft who many experts believed to be starting-caliber worthy. Needing a franchise quarterback, but not wanting to begin a long-term rebuilding process, Kelly believed he had to make a trade.

"We looked at everything, and we knew we weren't going to pick No. 1 or No. 2. So, and I've said it before, if you're not going to pick one or two, how do you go get a quarterback?" Kelly said. "Peyton Manning switched teams because of an injury. Drew Brees switched teams because of an injury. So we went down that path."

Lik Bradford, both Manning and Brees left their original teams after suffering serious injuries. Manning was released by the Indianapolis Colts in 2012 after missing an entire season due to a neck injury, and Brees left the Chargers in 2006 after suffering a dislocated shoulder and torn labrum and rotator cuff.

Brees and Manning were the only two quarterbacks who are not playing for their original teams to finish in the top-10 of total quarterback rating last season, Manning finished third and Brees fifth.

Kelly believes Bradford can have similar success now in a new environment. A consensus All-American and Heisman Trophy winner in college, Bradford certainly has the talent to be a franchise quarterback, the problem, however, has been his inability to stay on the field.

Bradford was drafted No. 1 overall by the St. Louis Rams in 2010, and won Rookie of the Year his first season. Since then he has played in just 23 out of a possible 64 games - including missing all of last season due to his second consecutive ACL tear.

Teams are typically weary of quarterbacks coming off of serious injuries, since many appear to be skittish while in the pocket when they initially return, something Kelly acknowledges, but isn't overly concerned about.

"That's happened, but I've also seen quarterbacks like Drew Brees come back with 25 staples in his shoulder and everybody said he would never play again," Kelly said. "You don't know. But that's a risk we were willing to take. You know it's a risk, but it was a risk we were willing to take."