Browns left guard Eric Steinbach turned up on Wednesday's injury report, listed as limited with a back injury.
Thursday, head coach Romeo Crennel revealed Steinbach twisted his back in practice. Steinbach sat out practice Thursday to continue recovering from the injury.
Starters D'Qwell Jackson (ankle) and Seth McKinney (shoulder) also missed practice. Both missed practice Wednesday as well.
Meanwhile, linebacker Antwan Peek arrived at the team training facility Thursday with swelling in his knee and sat out Thursday.
Finally, Leigh Bodden (back) was limited.
If Steinbach and McKinney both cannot play Sunday against Pittsburgh Crennel said the team would likely use Lennie Friedman at one guard position and Ryan Tucker at the other.
Tucker has played in a reserve role at right tackle since returning from a four-game suspension earlier this season. He practiced and played at guard during the '07 preseason.
Crennel said Isaac Sowells and Nat Dorsey also would be available.
It would be the first change to the team's lineup along the offensive line this season. The team has started the same five players in each game this year.
For the Steelers, Ben Roethlisberger (hip) and Willie Parker (knee) returned to practice Thursday after missing practice Wednesday. However, receiver Santonio Holmes popped up on the injury report and missed practice Thursday with a hamstring injury.
