The only certainty of Matt Barkley's football career has been that he would start at quarterback.

Not on Friday. For the first time in Barkley's career - a span that includes four years at Mater Dei High School in Santa Ana, Calif., and four seasons at Southern California - Barkley will come off the bench.

Eagles coach Chip Kelly has not announced how the quarterbacks will split playing time in the preseason opener against the New England Patriots, but Barkley has not taken a first-team snap all training camp. Barkley is expected to play after Michael Vick and Nick Foles on Friday.

"I'm not complaining," Barkley said. "I don't think that's my job. I'm just trying to do the best with what I am given, and I think Friday will be an opportunity for that."

Barkley said he did not come into training camp with expectations, although it was believed that Barkley would have a chance to compete for a starting job.

When Kelly was asked why Barkley has not received first-team snaps, the coach said, "Camp's not over." He reiterated that point when he was asked if the situation is representative of Barkley's performance.

"Camp's not over," Kelly said. "You'll see a lot of him on Friday night, though."

During the last two days, Barkley did not take any snaps during the main portion of 11-on-11 drills against the Patriots. He is relegated to watching from the sideline. As a quarterback, he needs to study Vick and Foles when they're leading the offense. But what Barkley took out of practice also came when the Patriots were on offense with Tom Brady.

"Just from watching him on the field, you see his release, his composure in the pocket, how calm he is, and at the same time he's explosive," Barkley said. "It's kind of an interesting paradox. He's kind of just standing back there, and then he whips the ball out."

Barkley also benefited from going against a different defense, even if he's playing with the third-team offense against the Patriots' third team. Barkley connected with Greg Salas on a deep pass that was one of the highlights of the morning practice.

Evaluating Barkley must be done with the understanding that he is not playing with the Eagles' top pass catchers, however depleted the unit may be. He said last week that he doesn't pay attention to the result of the play as much as the execution, because a receiver such as DeSean Jackson would run the route differently.

Barkley is careful to avoid saying anything controversial, even declining to explain what happened on a play in which the receiver ran the wrong route. He said the play was simply "incomplete."

The biggest area of growth for Barkley during the last two weeks has been his comfort with the offense, knowing the correct read to make and being systematic with how he approaches a play. He has learned to accept the shallow route if that's all that's available, and he has a better command of the offense.

But he's still not in contention to start, and the way the first-team snaps have been distributed is an indication. One injury or standout performance can change that, though, which is why Kelly's point about its being early in camp is valid. But for Friday, at least, Barkley will be a third-stringer.

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