Ben Roethlisberger rests ankle

PITTSBURGH -- Pittsburgh Steelers quarterback Ben Roethlisberger's sprained left ankle remained in a walking boot on Wednesday, and backups Charlie Batch and Dennis Dixon are preparing as if they'll play on Monday night in San Francisco.

Roethlisberger hasn't practiced since spraining the ankle in the second quarter of a 14-3 win over Cleveland last Thursday. He declined to talk to reporters before walking out of the team's facility with a noticeable limp.

Coach Mike Tomlin maintains Roethlisberger is "day to day" and will be evaluated throughout the week before a decision is made. Tomlin believes Roethlisberger doesn't need to undergo a full practice in order to play against the 49ers.

"He can be ready to play on a limited number of snaps," Tomlin said. "At the end of the week, when we get into some situational football things, that's going to require some physical preparation in some form or fashion. But we're going to take it day by day. We're always going to be optimistic when it comes to Ben."

Roethlisberger hasn't missed a start due to health reasons since a concussion sidelined him against Baltimore in 2009. He sat out the first four games of the 2010 season after violating the NFL's personal conduct policy and the Steelers went 3-1 in his absence with Dixon and Batch splitting the snaps.

Both expect to draw on that experience if called upon. The Steelers (10-3) are still hoping to catch Baltimore for the AFC North title and a shot at homefield advantage throughout the playoffs.

Batch threw two passes, both incomplete, while briefly relieving Roethlisberger against the Browns. Dixon hasn't taken a regular season snap since tearing the meniscus in his left knee against the Titans last September.

Though the 37-year-old Batch expects to be the starter if Roethlisberger can't go, there's a chance Dixon's mobility may help him get on the field anyway.

The Steelers have allowed 37 sacks this season, eighth-most in the league. Dixon's 26-year-old legs could be an asset, and for a player almost certainly in his last season with the Steelers, Dixon would love the chance to showcase his talents.

"I'm ready to prove to this team once again that I am ready to get things done," Dixon said. "I'm looking forward to it."

Neither player, however, has Roethlisberger's arm or uncanny ability to make things happen out of the pocket. If Roethlisberger can't play, it could drastically alter Pittsburgh's offense.

"Those guys, they're not Ben," wide receiver Mike Wallace said. "They're great players, but Ben is something really special. So you have to change your game to what they do best."

Wallace's preference would be to have Roethlisberger play, and he's shown a capacity to deal with significant pain. He's started all 13 games this season despite playing with a sprained left foot and a fractured right thumb. He even played the second half against the Browns, throwing for 178 yards with a touchdown and an interception while standing in the pocket on basically one leg.

"If he can play he will," running back Rashard Mendenhall said. "The only way he won't is if he can't. Last week with a high ankle sprain you could tell he was struggling but he was out there."

Center Maurkice Pouncey is also dealing with a sprained left ankle but is hopeful to play. So is linebacker LaMarr Woodley (strained left hamstring) and safety Troy Polamalu (right hamstring).

Polamalu didn't practice on Wednesday but expects to try later in the week. The long 11-day layoff between games is a bonus this late in the season.

The All-Pro also stressed his right shoulder is fine. TV cameras caught teammate Ryan Clark yanking on Polamalu's right arm against the Browns trying to get the shoulder back in place.

The only regular almost certainly out against the 49ers is linebacker James Harrison, who was suspended for one game by the league on Tuesday as punishment for his illegal hit on Cleveland quarterback Colt McCoy.

Harrison's appeal was heard by the league on Wednesday, but his teammates don't expect to see Harrison's familiar No. 92 until the suspension ends next Tuesday.