Washington Redskins cornerback Quinton Dunbar (23) has been placed on injured reserve due to a nerve issue in his leg. (Photo by John McDonnell/The Washington Post)

After weeks of monitoring a painful nerve condition in the leg of cornerback Quinton Dunbar, the Redskins decided to put him on injured reserve Wednesday, ending what had once been a promising season for him.

“When you’re talking about nerves, it worries me a bit,” Coach Jay Gruden said about Dunbar, adding that team doctors “haven’t been able to quite figure out a timetable” for his recovery.

Adding more to the team’s injury troubles, Washington also placed rookie wide receiver Trey Quinn on injured reserve after Quinn reinjured an ankle that he severely sprained in the season opener at the Arizona Cardinals. Quinn, who shined in the preseason as well as in the two games he played in November, aggravated his foot injury on Thanksgiving Day at the Dallas Cowboys and got progressively worse in last week’s practices.

“We knew it was going to be a slow-healing process,” Gruden said.

Eventually, the team thought it would be better for Quinn if he didn’t practice for the rest of the season.

To replace Dunbar, Quinn and guard Jonathan Cooper (who was also lost for the year with a torn biceps tendon in Monday night’s loss at the Philadelphia Eagles) the Redskins signed center Demetrius Rhaney, guard Zac Kerin and defensive end Marcus Smith, who was the Eagles' first-round pick in 2014.

Cooper was signed off the street Nov. 5 after starting guards Shawn Lauvao and Brandon Scherff suffered season-ending injuries and immediately started four games.

The decision to put Dunbar on IR turns the cornerback spot opposite Josh Norman over to a rotation of rookies in Greg Stroman, Danny Johnson and Adonis Alexander.

Several Redskins didn’t practice Wednesday, including center Chase Roullier, who is dealing with a knee injury and Gruden said “is limping around,” and guard Tony Bergstrom, who will miss at least two weeks with an ankle injury. Adrian Peterson, who often misses midweek practices, sat out with his shoulder injury. Also not practicing were linebacker Ryan Anderson (hamstring), defensive lineman Matt Ioannidis (shin) and safety Montae Nicholson (illness).

Limited were tackles Morgan Moses (knee) and Trent Williams (wrist and thumb), and cornerbacks Norman (hamstring) and Fabian Moreau (knee).

The Redskins did not put quarterback Colt McCoy on injured reserve, as they are holding out a small hope that his fractured fibula might heal enough for him to return before the end of the season.

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