Derek Wolfe was dealt another blow Friday when a medical exam revealed the Broncos' defensive end suffered a concussion, the team said.
Wolfe, already vexed by a four-game suspension after testing positive for a performance-enhancing drug, left Broncos practice early Thursday after a hit to the head.
He was carted off the field with a towel over his head. Two trainers, under each of Wolfe's arms, helped him walk to the locker room.
The team immediately put him through concussion protocols.
"He's still in the evaluation process," Broncos coach Gary Kubiak said Friday.
Wolfe in July was suspended without pay for the first four games of the season after the NFL said he violated the league's performance-enhancing drug policy.