Will the real Packers running back please stand up?

Or, for that matter, will any Packers running back that’s physically able to please stand up?

Until Sunday, only one of the five backs Green Bay had in training camp was playing free of injury limitations, and that was an undrafted rookie.

To reinforce the unit the team went out and got a free-agent veteran with 1,500 carries treading his 29-year-old wheels.

The signing ofCedric Benson on Sunday was a head-scratcher of a decision, but it was necessary to buttress the backfield.

Running backs had been dropping to the turf like European soccer players looking for a foul, and the team decided it needed to add another body. The body it added may be aging, but it is proven.

Benson rushed for more than 1,000 yards in each of the past three seasons. He is an established back who could spice up the competition.

The Packers entered training camp hoping to see something special from incumbent starter James Starks. Instead he was pedestrian in practice, disappointing in the first preseason game. Now he is out indefinitely with turf toe.

That leads to Alex Green. The second-year man out of Hawaii has looked brisk and bouncy, but he’s on a snap count, still limited by the ACL tear suffered last season.

 Brandon Saine the third-stringer has a hamstring injury and remains out another week or so. Of the two undrafted backs, only Marc Tyler is healthy, as Duane Bennett has a knee injury.

So what would have been a position battle anyway based on Starks’ decline and Green’s ascension has now turned into a position war of attrition. Who will be left standing when camp ends and who will have taken advantage of their opportunities?

Benson makes things interesting. He’s got a one-year contract with no bonus and no guaranteed money. He could just be a veteran presence to mentor the young guys and light a fire under Starks, a pawn the Packers can cut at the end of camp if they are unsatisfied. Benson could be the starting running back in the Sept. 9 season opener against the 49ers.

Green Bay probably won’t be able to sneak Brandon Saine onto the practice squad again this year -- he’s showed too much ability. Green and Starks are probably locks, though if Starks misses substantial time, the Packers have done more ruthlessly surprising things than cut a middling running back. 

As of right now, the guess is that Starks, Green and Benson make it, with one of the remaining three young players shepherded onto the practice squad for insurance. That’s highly subject to change, of course, as Benson gets acquainted and injuries play out. Tune in next Monday for an updated evaluation.

For up-to-the-minute Packers updates, follow James Carlton on Twitter at @CBSSportsNFLGB.