The former Trojans are teammates now, and they're battling for the same job.
Sanchez, a 2009 first-round pick who led the New York Jets to consecutive AFC championship games in his first two NFL seasons, signed a one-year contract with the Philadelphia Eagles in March. Nick Foles is the starter after a sensational breakout year, so Sanchez will compete with Barkley for the backup spot.
''If my role is going to be to help Nick get ready for the season, help Nick get ready for Week 1 or preseason games, I'm going to be ready for whatever they need me to do,'' Sanchez said during his first organized team activities with his new team. ''It's nice to be with somebody like Nick who really works hard, who wants to compete, who wants to throw a couple extra after practice.''
Sanchez spent last season on injured reserve after tearing the labrum in his right shoulder in a preseason game. Geno Smith took over as the starter for the Jets, and they signed Michael Vick from the Eagles early in free agency, making Sanchez expendable.
He quickly landed in Philadelphia, where he gets a chance to play in Chip Kelly's up-tempo offense. Sanchez saw it in college from the opposite sideline when Kelly coached at Oregon.
''I think what they did last year was just the tip of the iceberg for these guys,'' Sanchez said. ''If we continue to work, if we continue to improve, that was the real enticing thing.''
Barkley was pressed into action as a rookie when Foles and Vick were injured last year. He threw four interceptions and lost a fumble in four quarters over two games.
He's far more comfortable this time around.
''It feels like my offense now,'' he said. ''Last year, it felt like it was Oregon's offense. It feels like the offense that I've been running for a while now. All of the calls, all the checks, it just comes to you quickly without having to think about it now.''
Barkley could've been a top-five pick if he left school after his junior year, but he returned as a Heisman Trophy front-runner with a chance to lead USC to a national championship. Neither happened, and Barkley finished his career watching his teammates play in a bowl game from the sideline with his arm in a sling after a shoulder injury.
There were questions about his arm strength last year, but Barkley said he's pain-free and feels fine now.
''I feel like I have more torque, more velocity on the ball,'' he said. ''I feel confident in being able to put it anywhere I need to.''
Barkley rewrote the conference record book during a USC-record 47 starts over four seasons, becoming the Pac-12's leader in touchdown passes, yards passing, completions and total offense. He impressed Kelly in four games against Oregon and was selected in the fourth round.
Foles, a third-round pick by Andy Reid just a year earlier, began the year as Vick's backup before taking over in October. Foles led the Eagles to the NFC East title and threw 29 touchdowns and only two interceptions in 11 starts, including a playoff loss to New Orleans. He also had the third-highest passer rating (119.2) in league history.
But with injuries always a risk, Kelly wanted depth behind Foles.
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