Garrett Gilbert replaced Mayfield for the final two plays of the half as Mayfield left for the locker room holding his hand.
Mayfield went 10-of-17 for 98 yards and a touchdown in the first half.
If he can’t return in the second half, it will be Gilbert against Devlin Hodges.
The game was something of an afterthought after what happened two weeks ago, but the Steelers scored a tying touchdown with a minute left in the first half on a 30-yard pass from Devlin Hodges to James Washington. Washington made a spectacular catch while being interfered with by T.J. Carrie.
The Steelers had only 9 yards on their first two possessions and trailed 10-0, but they scored on their final two possessions of the first half.
The Browns’ touchdown came on a 15-yard pass from Mayfield to Kareem Hunt.