No team runs the ball like the Pittsburgh Steelers. Although offensive coordinator Bruce Adrians seems intent on beefing up the passing game, Mike Tomlin has repeatedly expressed his love for attrition football.

Last year, the Steelers were in no position to play attrition football. In fact, they gave up several games in the fourth quarter. There are many reasons for these late game give aways, one of those is that they lacked the backfield to pound opponents into submission.

Until Verron Hayes rejoined the team late in the season, the team’s backfield did not feature a single back that had been drafted by the Steelers. In fact, only one of their backs, Najeh Davenport, entered the NFL through the draft. The rest were rookie free agents.

One offeseaon has seen a dramatic change with the Steelers selection of Rashard Mendenhall in the draft and the signing of Mewelde Moore, who was Minnesota’s 4th round pick in 2004.

That gives the Steelers Willie Parker, Rashard Mendenhall, Mewelde Moore, Najeh Davenport, Cary Davis and Gary Russell. (They also have Billy Lasto and Justin Vincent, neither of whom figures to hold a roster spot beyond the first mandatory cuts.)

• That leaves six backs when the Steelers normally carry only five. Who is the odd man out?

Baring injury, Parker and Mendenhall are both locks to make the 53 man roster. You’d have to figure that Moore is too, given that the team invested significant money to sign him. He’s also projected to work as a kick returner, which is certainly a need area.

• That leaves Davenport, Russell, and Davis. Who is more expendable?

Carey Davis would appear an inside track on staying, by virtue of his play at fullback last year. Dan Krieder currently off the roster, Davis would figure to inherit the starting role. Davis averaged four yards a carry, but only had 17 of them. Davis got the nod over Krieder at certain points because of his supposed versatility, but he never did much to justify the coach’s faith in him.

The easy money would peg Gary Russell as the prime candidate depart. He played little last year, only rushing the ball 7 times for 21 yards. Russell’s potential is his upside. He drew comparisons to Barry Foster during preseason last year, and he only played two years in college. Russell has more room to grow.

Then there’s Davenport. Steel Curtin Rising speculated that the signing of Mewelde Moore might have signaled the beginning of the end for Davenport. Yet that was before that draft. Ironically, it’s conceivable that Mendenhall’s arrival actually favors Davenport making the team.

The logic is that while Davenport will never give the Steelers the 1-2 punch capability they wanted, his 500 yards, 4.7 yards rushing average, and combined 7 touchdowns do show that he can be a role player. Perhaps Mendenhall gives Davenport room to be that kind of role player. Perhaps not.

• Heading into the Steelers OTA’s (or mini-camp as they used to call it) the weeding out process at running back comes down to three things.

Who plays full back? Here its hard not to make a sentimental plea for Dan Krieder’s return, as the man embodies attrition football. But even if Krieder is fully recovered from his injury, as Kevin Colbert asserts, one has to wonder if how much longer he’ll use his body as a human battering ram.

• Davis has a year under his belt at FB, but he did nothing to dazzle. If Russell or Davenport can fill that role Davis could be in trouble.

Salary cap impact is the next factor. The Steelers have invested serious money in Parker, Mendenhall, and Moore. Throw in the reality that they’re paying Max Starks seven million dollars and projecting him as a back up. The team also might want to dip into the free agent pool to sign Anthony McFarland or some other offensive or defensive lineman. Najeh Davenport reportedly makes a million a year, and could easily become a cap casualty.

Finally, there is special teams. The Steelers sorely lacked special teams stand outs in 2007. If any of the three men demonstrates an ability to make an impact on special teams its safe to assume he will greatly enhance his prospects of making the team.

The success or failure of the Steelers running game hinges more on the offensive line’s run blocking, Willie Parker’s ability to bounce back from injury, and Mendenhall’s development, than who occupies the back up spots.

Nonetheless, one of the tricks to winning in the salary cap era is stocking your team with back ups that provide the best bang for the buck. Finding those players is what needs to guide this back up running back competition.

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