Kevin Kolb and Stephon Gilmore both had to leave the Buffalo Bills' pre-season game early because of injury.
The quarterback exited in the first quarter with concussion symptoms, after taking a blow to the back of the head while scrambling for a first down, while Gilmore took a knock to the wrist.
Kolb, who is competing with EJ Manuel to be the team's starter for the coming season, has already missed time during training camp with a knee injury.
The Bills will finish their pre-season against the Detroit Lions on Thursday.
