On the roster: Doug Martin, Mike James, Brian Leonard, Michael Smith, Jeff Demps, Erik Lorig.

With Doug Martin the Tampa Bay Buccaneers have a clear feature back, but behind him the talent doesn't run very deep. Erik Lorig is the starting fullback, but because I don't want to write a separate article for one fullback he's on this list too. There's a theoretical possibility that he loses out to Brian Leonard.

Who will be the backup?

Doug Martin will be the starter. There's no doubt about that. But we have three running backs battling for the backup job. The Buccaneers have made it clear that they think rookie Mike James can fill in for Martin on occasion, and be the guy if the Muscle Hamster gets injured. But that's a lot to ask of a back who never topped 650 yards in college and managed just 4.2 yards per carry in his final season.

But who else is going to win that job? The dimunitive but speedy Michael Smith, last year's seventh-round rookie who couldn't win a starting job in college and who couldn't get on the field last season? That seems unlikely. Meanwhile Brian Leonard has been largely useless as a runner in the NFL, averaging a pitiful 3.7 yards per carry in his career. Jeff Demps might have a tiny shot at a role, but he will more than likely miss all of training camp due to his track career. Which means his chances are more or less nil.

Can Brian Leonard challenge Erik Lorig?

I don't see it. Leonard hasn't been a fullback in the NFL since he left the Rams in 2009, and he wasn't all that good as a lead blocker when he was the fullback in St. Louis. Leonard has been a very productive third-down back, though, and can be an asset in the passing game. Greg Schiano has referred to him as a bit of a hybrid, and perhaps the Buccaneers plan to use him that way. But Lorig was a traditional lead fullback last season and an effective blocker, whose vision does need to improve. Unless the Bucs move away from using a lead fullback frequently.

Who will be the third-down back?

Brian Leonard is most likely to win this role, but the Bucs have a number of players who could fulfill this role. Doug Martin himself was extraordinarily productive in the passing game last season, but the team still used D.J. Ware as the main third-down back. Brian Leonard has been that guy for the Cincinnati Bengals over the past years and has done a pretty good job in that role. He could step into that role fairly easily.

But the two inexperienced guys have something to offer, too. Michael Smith has the speed to be a threat in the passing game, although he may be too small and inexperienced to be an effective pass blocker. Mike James is a rookie and rookies struggle notoriously on third down -- but he did catch 30 passes last season and has the special teams experience that suggests he has the physicality to be a decent blocker. As usual, Demps can basically be crossed off the list because he likely will miss training camp.

Special teams value

When you can't win on offense, you can win a roster spot on special teams. And each of the Bucs' running backs has value, there. Michael Smith has the speed to be a good kick returner, but he is limited by his size in basically every other special teams role. The same is true for Jeff Demps. Brian Leonard has been a core special teams player in the past, while Mike James was compared to Earnest Graham by Mark Dominik. The latter two should do very well on coverage teams, but won't do much as returners.

Roster projection

Doug Martin is a slam dunk, and I'll give Mike James and Brian Leonard the advantage over Michael Smith. Jeff Demps doesn't have much of a shot because he'll miss most of training camp.

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