PHILADELPHIA -- The Eagles’ offensive line depth is about to get tested.

Right guard Andrew Gardner, one of the new starters this season, injured his foot early in the Eagles’ 24-17 victory over the New York Jets on Sunday. ESPN’s Adam Caplan reports that Gardner is expected to miss an extended period of time.

Matt Tobin, who filled in for Gardner on Sunday, likely would move into the starting lineup. Tobin moved over to left tackle when starter Jason Peters was injured later in the game. That’s a further indication that Tobin is at the top of the coaches’ list among the backup linemen.

Tobin and Gardner were the first backups to step in last season, when injuries claimed guards Evan Mathis and Todd Herremans, as well as right tackle Lane Johnson.

During the offseason, Eagles coach Chip Kelly decided to part ways with Mathis and Herremans. He didn’t draft a single offensive lineman or sign any linemen in free agency. His plan all along was to promote Gardner and Allen Barbre to starting guard spots.

Guard play was an issue as the Eagles struggled in the running game over the first two weeks of the season. On Sunday, the Eagles got their running game going with Ryan Mathews replacing the injured DeMarco Murray at running back.

The line was not noticeably affected by the absence of Gardner and the addition of Tobin. But the injury to Gardner does move the Eagles one player closer to the end of their bench.

Dennis Kelly came in at right guard when Tobin moved to left tackle. Josh Andrews likely would be the next player in line if another guard were to be injured. Andrews, who was on the practice squad last year, made the team as a reserve this year. He has never played on offense in an NFL game.