Redskins tight end Chris Cooley left Sunday's loss to the Colts with a concussion.
Cooley, who had five catches for 37 yards, suffered the injury in the second half.
"I just know it was a concussion, and he could not go back in. I knew just looking at him -- you could tell that there was something wrong," Redskins coach Mike Shanahan said.
"I really don't know when it was. I just looked at him on the sideline and could tell that there was something wrong."
Cooley Suffers Concussion In Loss