Steelers RB Rashard Mendenhall is set to play in the Sunday night showdown against the Baltimore Ravens. Mendenhall says his Achilles has "been feeling good" and there's been "no setbacks."

Mendenhall was officially called probable by the Steelers on Friday after he made it through a full week of practice unscathed. Mendenhall missed the previous four games -- all Pittsburgh victories -- with an injury suffered in a loss to the Tennessee Titans last month.

"He looks good," backup RB Isaac Redman said. "We're definitely well-prepared for this week for the running game."

Indeed. Redman said the Steelers will dress Mendenhall, Redman and RB Jonathan Dwyer for the same game for the first time this season. Mendenhall is a former first-round pick and 1,200-yard rusher, Dwyer and Redman each have had 100-yard rushing games during the Steelers' winning streak.

"Those guys (Redman and Dwyer) came in and showed themselves well," Mendenhall said. "As far as me, I just want to continue to work and do whatever I can."

Redman said the Steelers will keep all three backs as fresh as possible. Throughout the season, Pittsburgh has tended to give carries to the proverbial "hot hand" during games in which two of the above three were active (and even to RB Baron Batch).

In Monday's 16-13 overtime win over the Kansas City Chiefs, for example, Redman started but it was Dwyer who ended up getting more carries and yards after Redman was ineffective.

Redman and Dwyer have said they consider Mendenhall as the feature back. If the Steelers know the direction they are leaning Sunday, they aren't tipping their hand.

"I don't pay attention to any of that at all," Mendenhall said. "For me, I just want to continue to work and prepare myself to do whatever I can."

Clark to play: FS Ryan Clark understands that the fact he's had two concussions in such close proximity to each other (Oct. 28 and Nov. 12) could appear alarming from the outside.

Clark even acknowledged he's "going to be messed up later" in life. But after a symptom-free week of practice, Clark is probable to play Sunday against the Ravens.

"They said I'm cleared to play, easy as that," Clark said. "I went through the battery of tests and I was cleared to play. I feel fine. If I felt in any way symptomatic of what was going on I wouldn't play. But I don't. I feel fine. For me, it's impossible to stay on the sideline without someone making me, if I'm good to go.

Clark is wearing a larger, more-padded helmet from now on.

Other injuries: As expected, QB Ben Roethlisberger (shoulder/rib), WR Antonio Brown (ankle), S Troy Polamalu (calf) and RT Marcus Gilbert (ankle) have been ruled out for Sunday's game.

Also as expected, DE Brett Keisel (shoulder), CB Ike Taylor (illness), LT Max Starks (ankle) and dime CB Curtis Brown (quadriceps) are listed as probable after practicing fully Thursday and Friday. Reserve LB Stevenson Sylvester (hamstring) is questionable.

Leftwich has butterflies: Set to make his first NFL start in more than three years, QB Byron Leftwich welcomes that familiar nervous feeling he's always had on game days in which he knows he's going to play.

Leftwich got a full week of practice in working with the first-team offense. He'll make his first start with the Steelers in what is his fourth season with the team (his last start game in September 2009 with Tampa Bay).

"Butterflies will come around Sunday," Leftwich said. "That's a good thing -- I get them every time I play. I'm excited, I think we're excited, I'm quite sure they'll be excited."

Follow Steelers reporter Chris Adamski on Twitter @CBSSteelers and @BuzzsawPGH.