Parker has played only once since spraining his knee Sept. 21 in Philadelphia, running for 70 yards in a Monday night win over the Washington Redskins on Nov. 3 in which he dislocated his shoulder.

"The shoulder popped out briefly during the course of the Redskins game and it popped back into place," Tomlin said, denying reports that Parker had a torn labrum. "Adrenaline or what have you didn't allow him to recognize it during the course of game. He came in (last) Tuesday, took a look at it and of course it was very painful."

Parker was leading the NFL in rushing last season before breaking his leg during the next-to-last regular season game in St. Louis. He has 333 yards and four touchdowns on 87 carries this season.

With rookie Rashard Mendenhall out for the season with a broken shoulder, Mewelde Moore has been Pittsburgh's featured back in three of the past four games. Although he has scored six touchdowns, the Steelers' rushing offense has struggled in recent weeks, totaling only 214 yards on the ground the past three games.

The return of left tackle Marvel Smith could help the running game. Smith hasn't played since Oct. 5 because of a back injury, but Tomlin said it's possible he will practice this week. Smith had a favorable workout Tuesday, Tomlin said.