Matt Barkley, Tim Tebow in competition for No. 3 quarterback job

The top two quarterbacks on the Eagles will be Sam Bradford and Mark Sanchez, unless injury strikes either player. The competition for the No. 3 quarterback spot is less clear.

Matt Barkley is the longest-tenured Eagles quarterback and entering his third year with the team, but he has not been able to graduate to the No. 2 job since coming to Philadelphia. Tim Tebow is competing with him, and could offer more versatility at the third quarterback spot. Coach Chip Kelly said Tebow is being evaluated as a quarterback, and the position is as a quarterback. But Kelly always says the more a player can do, the better. And Tebow can be used in ways other than a traditional quarterback.

"Tim obviously has a lot of skills that other quarterbacks don't have because of his ability to run the football," Kelly said Thursday. "But we haven't delved into any of that. ...We haven't spent any time as an offensive staff looking at how we can do this, or what can we do working out how the final roster is going to express itself."

Don't dismiss Barkley, though. If the question is passing ability, Barkley has appeared to be a superior passer since the spring. Kelly also pointed out that he has the most experience in the offense of any quarterback on the roster. Barkley is healthier and stronger than at any other point in his Eagles career. The team invested a 2013 fourth-round pick in him and remained patient during Barkley's rookie season, when he was still recovering from a shoulder injury.

"A really, really good April to June for us," Kelly said of Barkley. "I thought it was a big improvement from where he was."

Kelly said it's difficult for all the quarterbacks to get into a rhythm because they're rotating in and out of the lineup. He added that the evaluation of them will come in the preseason games, because the true measure of a quarterback is seen when there's a live rush. No matter how much practice simulates game action, the quarterback is still wearing a red jersey.

"The big performance and all the other guys is when we finally get a chance to go against the Colts in the first preseason game, and then the Ravens, and then the Packers, and then the Jets," Kelly said. "For any quarterback, you're still wearing a red jersey. Even when the rush comes clean, [the defense is] going to pull off and kind of get away from you. But it's not going to be like that when they get into those preseason games."

This competition could come down to the final preseason game against the Jets, when the Eagles play the backups. Last season, Kelly kept his top two quarterbacks out of the lineup for the fourth game because he already knew what he had in Sanchez. That could be the case again this season.

Kelly tries to promote competition, and he said it's an open race for the No. 1 job -- even though it appears in line to go to Bradford, as long as Bradford is healthy. That means the most intriguing quarterback competition on the Eagles' roster is for the No. 3 job. It will likely stay that way until the roster is cut to 53 players.