Geathers has been ruled out for the rest of the game.
An announcement on his injury came with about two minutes left in the first half, and one play before the Steelers tied the game at 10.
Geathers appeared to get injured about four minutes prior, when he and teammate Reggie Nelson collided violently as they tried to help defensive end Carlos Dunlap wrap up Steelers wide receiver Jerricho Cotchery on a pass that went for a 5-yard loss along the Bengals' sideline.
Just after the play, Geathers and Nelson jumped right up off the ground. Geathers ended up jogging down the bench as it appeared he tried to shake loose the pain of the contact. The backup defensive end had not yet figured into Cincinnati's game statistics, but was playing often in a rotation with other linemen.
Bengals receiver Marvin Jones also left the game, but was expected to return. He was getting treated for cramps in the locker room.