Pittsburgh Steelers running backs are seemingly spending more time with doctors and trainers than they are on the practice field.

No worries. Second-year RB Baron Batch, FB Will Johnson, and rookie RB Chris Rainey have been handling the heavy lifting until their teammates return from injury. The Steelers can also add third-year RB Jonathan Dwyer to that list after he returned Thursday from a shoulder injury.

“It’s all about preparing and coming out to work every day like you’re the starter,” Batch said Thursday at St. Vincent College in Latrobe, Pa. “As a group and as a room, and as a team, I think we have a lot of guys that do that.

“It doesn’t happen on gameday, it happens in practice, so I’m going to keep preparing like I’m going to have to step up.”

Starting RB Rashard Mendenhall tore his anterior cruciate ligament (ACL) in the final game of the regular season. He started training camp on the physically unable to perform (PUP) list, working out on adjacent fields during afternoon sessions, but he hasn’t practiced with the team and isn’t expected to be ready for the opener Sept. 9 at Denver. Second-year RB John Clay also tore his quad during practice on Sunday and is gone for the season.

Mendenhall’s backup RB Isaac Redman was the projected starter, but his status is uncertain after battling a nagging groin injury that’s to the point where he was scheduled for a precautionary MRI Thursday morning.

Steelers’ head coach Mike Tomlin classified Redman as day-to-day, but the undrafted running back from Bowie State said he likely isn’t practicing Friday, meaning he probably won’t play in the team’s second preseason game against Indianapolis Sunday at Heinz Field.

The good news, Redman said, is that he likely won’t be out long-term or need surgery, and that he could be back to practice as early as next week.

“Hopefully I can get through this rehab and do what I need to do to get healthy,” Redman said.

Dwyer was initially part of the walking wounded after injuring his shoulder during the first preseason game last Thursday against Philadelphia, but he returned to practice a week later.

“He worked a full day and he’s in the mix for Sunday night,” Tomlin said.

Dwyer dazzled while taking first-team snaps Thursday, starting 11-on-11 drills with a one-handed grab on a swing pass out of the backfield. Later, Dwyer’s sharp against-the-grain cut helped the offense get out of the end zone, while working in the shadow of its own goal post.

That bottled up emotion drove Dwyer crazy while injured and on the sideline for most of the week.

“I want to be a contributor,” Dwyer said. “I hate sitting out. I’m just trying to be more prepared mentally and keep up with my conditioning and therapy and do what they ask me to do.”

With Dwyer working in a limited capacity this week, the bulk of the work went to Batch, a former seventh-round draft pick, who was the darling of training camp last season until a torn ACL derailed what looked to be a promising rookie campaign.

“I feel like I have a lot to prove and I’m going to do that,” Batch said. “I worked way too hard not to be out there, so I want to get every rep I possibly can.”

That shouldn’t be a problem with a limited backfield. But there are concerns that the workload is too heavy for the running backs and the increased number of repetitions might wear out younger players.

Batch doesn’t see that as a problem for him.

“You have to take care of your body,” Batch said. “It starts there and you have to be mentally tough, so I try to do those things.

“This is my job and I love what I do. I love being out there.”

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