Chris Polk, left, has 36 yards on five carries and one touchdown this season. (USA Today Images)
Updated 1:27 p.m.
The Eagles have ruled running back Chris Polk out for their game Sunday against the Cowboys and promoted running back Matthew Tucker from the practice squad.
To make room for Tucker, an undrafted rookie free agent from Texas Christian, they released cornerback Jordan Poyer, a rookie seventh-round pick who has played in only one of the last four games.
Tucker, 6-foot-1, 230 pounds, rushed for 2,602 yards and 33 touchdowns during his four-year career at TCU.
Tucker ran 25 times for 89 yards and two touchdowns in the preseason. He was released on Aug. 31 as part of the final cutdown to 53, then signed to the practice squad the next day.
Poyer played 17 snaps at cornerback in the opener vs. the Redskins but has not gotten onto the field on defense since. He’s played only 16 snaps this year on special teams. He was inactive for the Chiefs and Buccaneers games and in uniform but did not play against the Giants.
As a rookie, Poyer is subject to the NFL’s waiver claim process. If he clears waivers, he’s expected to rejoin the Eagles on the practice squad, at least for as long as Polk is hurt.
Polk, who injured his shoulder during the game in Tampa last weekend, was listed as questionable in Friday’s injury report and was listed as a full participant in the team’s Friday walkthrough.
Polk has 36 yards on five carries, including a 28-yard gain and a touchdown against the Broncos, along with two receptions for 19 yards.
Polk is also one of the Eagles' top special teamers. He's played in 94 of 196 special teams snaps this year, ninth-most on the team.
Polk missed practice Wednesday, was limited Thursday and a full participant Friday.
The Eagles still list quarterback Michael Vick (hamstring) questionable and safety Patrick Chung (shoulder) doubtful, but they haven’t officially ruled either one out for Sunday.