TAMPA – A running back stole the show the last time the University of South Florida football team played a game.

But on Tuesday, four days before USF’s season opener against Stony Brook, first-year coach Skip Holtz remained uncertain who will start at halfback: Mo Plancher, Bradley Battles, Demetris Murray or Marcus Shaw?

“If the game was tomorrow, I would start Battles,’’ Holtz said.

In reality, the battle to start Saturday is between Battles and Plancher, who started all 13 games last season. Murray had a strong spring and had moved ahead of Battles entering fall camp, but Battles shined in a pair of recent scrimmages to jump ahead of Murray and Plancher.

A sixth-year senior, Plancher has been limited by a shoulder injury during the second half of fall camp and just returned to contact drills in Friday’s scrimmage. Meanwhile, Shaw is a true freshman who Holtz says will likely play Saturday, but the coaching staff knows Shaw isn’t ready for a starting job only a few months out of De Soto High in Arcadia.

“The running back situation is by committee right now,’’ Holtz said.

The way the Bulls ended last season, their backfield seemed in good hands for 2010.

In USF’s win over Northern Illinois in the International Bowl in January, junior Mike Ford carried the Bulls to victory with a career-high 207 yards, earning MVP honors. However, only a few weeks later, Ford was dismissed from the program for off-the-field issues.

The Bulls avoided a total disaster when Plancher was granted a sixth year of eligibility by the NCAA in the spring after another upperclassman expected to compete for a starting job, Jamar Taylor, left the program. The loss of Ford, Taylor and often-injured Aston Samuels – he left the program over the summer – left Plancher as the projected starter. Plancher rushed for 581 yards a year ago.

“As a sixth-year player, I think he’s got the all-around game savvy that he can handle all situations: run, pass, catching,’’ offensive coordinator Todd Fitch said. “We’re going to need all three of those guys to be there.’’

Still, at 5-foot-8 and 195 pounds, Plancher’s carries must be monitored to keep him fresh. Battles (5-8, 201) and Murray (5-10, 206) are a little bigger and faster, but Battles is a redshirt freshman and Murray only a sophomore who saw limited action last season.

Plancher says the competition in camp has been good for everyone considering the circumstances.

“I see a lot of hard work and determination,’’ Plancher said. “These guys are hungry. Every day they come out and fighting. I see them getting better. They are night and day from last year. They are running more physical and they are blocking better.’’

The lack of a feature back raises questions about the plan to reduce quarterback B.J. Daniels’ role in the running game. Daniels led the team in rushing last season with 772 yards, but Holtz and Fitch don’t want a repeat peformance.

“I can understand why B.J. has been our leading rusher,’’ Holtz said. “He is a hard son of a gun to tackle. He can make an awful lot of things happen, and he can really make this offense move with what he can do with his feet.

“We need some others to help him out, though.’’

Fitch agrees, knowing how much Daniels already has on his plate running a new offense in the passing game.

“We hope as this thing unfolds as the season goes, [B.J.] will be a small portion of our running game,’’ Fitch said.

At this point, the best-case scenario for Stony Brook and beyond is for Plancher’s shoulder to hold up well and while Murray, Battles and Shaw get some carries and much-needed experience.

“It’s real important to me,’’ Plancher said of having a strong final season. “Football is a big part of my life, and I wanted to come back and help the team. It’s a big opportunity. I’m just going to take it and run with it. It doesn’t matter if I get five carries, 10 or 20, it really doesn’t matter.’’

While Holtz would prefer a featured back like he had at East Carolina in reigning NFL MVP Chris Johnson, he isn’t all broken up that Plancher had to sit much of fall camp.

“It’s gotten Murray and Battles and the guys behind him an awful lot of work,’’ Holtz said. “[Mo] should be fine. We’re just being protective with him to try and develop depth.’’