TAMPA, Fla. -- We continue our position-by-position look during the break between minicamp and training camp with the Tampa Bay Buccaneers' running backs.

At first blush, this unit appears to have plenty of depth. But when you think about it, none of the running backs were very productive last season. The Bucs are hoping that improves without major personnel changes in the backfield. An overhaul of the offensive line should help, but the running backs need to be more productive.

The Bucs have been firm in saying Doug Martin remains the starter. Once upon a time (2012), Martin looked like a true feature back. But he hasn’t been very good the past two seasons. He needs to bounce back quickly, because the coaching staff really likes second-year pro Charles Sims, who could end up ahead of Martin on the depth chart.

After Martin and Sims, things could get a little cloudy. Bobby Rainey and Mike James could be competing for one position. Rainey might have the edge because he’s more versatile and can do a lot on special teams. But the Bucs like James as their big back.

The Bucs also are likely to carry one fullback. It will be either Jorvorskie Lane or rookie Joey Iosefa.