Redskins tight end Chris Cooley sustained a concussion during the second half of Washington's 27-24 loss to the Indianapolis Colts on Sunday night and didn't return to the field.
He had five catches for 37 yards.
"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 entered the game second on the Redskins with 23 catches for 303 yards and two touchdowns.
Two key members of the Colts were injured. Running back Joseph Addai hurt his shoulder in the second half, and receiver Pierre Garcon hurt his right ring finger in the first.
Addai was helped off the field and didn't return. He exited the Colts' locker room after the game with an ice wrap on his left shoulder, according to *The Indianapolis Star*.
Colts coach Jim Caldwell wouldn't go into specifics about the nature of Addai's injury.
"When he was walking off the field, the kind of pain he was in ... let's hope it's something that's not serious," Caldwell said.
Garcon said his finger wasn't broken. He said he would take some painkillers for the finger and "see how it feels ... play it day by day, really."
Before leaving, Addai carried 17 times for 128 yards and a touchdown, while Garcon had four catches for 103 yards and a score.
The Associated Press contributed to this report.