Both rookies Isaac Redman and Tank Summers are pushing hard for roster spots with the Steelers but there may only be one spot available.
Willie Parker, Mewelde Moore and Rashard Mendenhall are guaranteed roster spots. Fullback Carey Davis isn't outstanding in any one phase - though he does have the best hands among the running backs - except on special teams, where he's one the team's leaders.
That could leave Justin Vincent – who's been on the practice squad the past two years – Summers and Redman fighting for one spot on the roster and one on the practice squad.
Redman has impressed as a runner. He's both tough and physical and has a running style similar to former star Barry Foster. He's got great lean and leg drive.
Summers, meanwhile, is being tried as a fullback and has also looked good as a special teams player.
Vincent isn't just a throw-away player either. The former LSU star knows the offense and got nine carries in the preseason opener.
The question is whether the Steelers feel Summers could be a capable replacement for Davis. Fans seem to think so but the coaching staff may not feel the same.
It's going to be something that bears watching as the team heads into its final three preseason games.