The Eagles signed safety Jerome Couplin off the Detroit Lions' practice squad to fill the roster spot that opened when they cut Roc Carmichael on Tuesday.

Couplin, who is 6-foot-1 and 215 pounds, played eight games for the Lions this season and had two tackles. He went undrafted in May out of William and Mary.

"Big, tall safety," coach Chip Kelly said. "We think he's got potential. The only way you can get a guy like that is you have to add him to your active roster."

Couplin does not yet have a specific role, and the signing appears to give the Eagles a prospect to evaluate for the future. Kelly mentioned the possibility of looking at Couplin in the dime formation. Couplin played in goal-line situations and on special teams in Detroit but was eager to see where he fits with the Eagles.

Couplin practiced Wednesday. He is the fifth safety on the roster. Cornerback Jaylen Watkins, the Eagles' fourth-round pick, has also worked at safety during the last few weeks. The Eagles signed Couplin over promoting Ed Reynolds, the fifth-round pick on the practice squad.

"That has nothing to do with [Reynolds]," Kelly said. "We could not get Jerome unless we put him on our active roster. We couldn't bring him over to our practice squad. . . . If we need to have a safety go play next week, then we can make a maneuver and make Ed active and put somebody down."

Grieving McCoy

Eagles running back LeSean McCoy played against the Seahawks on Sunday while grieving the death of a cousin. McCoy said Wednesday that he feels better after spending time thinking and being with his family.

He did not want to use the way he felt as an excuse for his 17-carry, 50-yard performance. However, he said that he's a lot more focused and that his preparation has been "excellent" this week.

"I know my cousin would like to see me move on to how I am as a player, person," McCoy said. "The smiling, happy-go-lucky teammate I've always been and how I am now. I've just got to move on. I know a big game will make him happy."

McCoy rushed for 159 yards and one touchdown in the Thanksgiving game against Dallas.

Injury updates

Kicker Cody Parkey (right groin) and running back Chris Polk (ankle) were limited in practice. Wide receiver Josh Huff (hip) was a full participant.