The Steelers won 28-10.
Cribbs, running his first play of the game out of a Wildcat formation, was about to be tackled by LaMarr Woodley before Harrison slammed into the left side of Cribbs' helmet. Cribbs fumbled after gaining 1 yard, but the Browns recovered.
After going to the sideline, Cribbs was examined by the Browns' medical staff for several minutes. He was then taken to the locker room for further tests, most likely to determine if he has a concussion. The Browns said he would not return to the game.
Later in the quarter, Harrison slammed into wide receiver Mohamed Massaquoi after a pass from Colt McCoy touched his hands, causing the ball to come loose. The pass was ruled incomplete. Massaquoi did not stay down for several minutes as Cribbs did, but was taken to the locker room for examination.
The injuries left the Browns with two healthy receivers at the end of the first half, Brian Robiskie and Chansi Stuckey. Carlton Mitchell, the only other wide receiver on the active roster, was not in uniform.
Information from The Associated Press contributed to this report.