July 26, 2014 at 1:00 am

Lions training camp position previews: Running backs

This is the sixth in a series of position previews in advance of Lions training camp. Today: Running backs. See the roster breakdown in the gallery above or by clicking here .

The Lions’ use of running backs will look thoroughly different under new offensive coordinator Joe Lombardi.

When Lombardi was in New Orleans, the Saints mixed in three or four backs each game, as well as a fullback, and each back had a variety of assignments.

The most likely scenario in Detroit is for Joique Bell to play the Pierre Thomas role as the “starter” who receives the bulk of the inside carries, particularly on first and second down, while also being involved in the screen game.

Reggie Bush fills into the Darren Sproles role as a player who’ll receive some carries but often line up as a receiver and be dangerous on third down. The most carries Bush had during his five seasons in New Orleans was 157, and even though he’s a better runner now, he’s still most effective in space.

Then there’s Theo Riddick, who will earn more playing time because of his versatility as a runner and potential slot receiver. Riddick looked great during the offseason, and after being the No. 3 back out of camp last year, there’s no reason to expect a change in 2014.

If the Lions use their backs like the Saints, there will be many times where two backs will be on the field together. Bell and Bush could both be in the backfield, Bush and Riddick could line up out wide, Bell could be out wide with Riddick in the backfield — the options are endless.

Mikel Leshoure remains the most likely backup for Bell’s role, but Riddick’s special teams ability likely means Leshoure has to wait for an injury to crack the active roster.

The fullback role, which will most likely be filled by Jed Collins, will come mostly in short-yardage situations, but he will also be involved as a receiver out of the backfield.

Film review

Although Bell will be 28 by the time the season starts, he’s effectively entering his third year as a running back in the NFL.

During his first two seasons with the Lions, Bell had a lot of success running between the tackles and gaining big chunks on screens, but he could still improve his downfield vision.

One of Bell’s top traits is an ability to gain as much as possible in tight situations, either by running through small gaps or breaking through tackles. However, there were some screens — almost always to the right side — last year that could’ve been touchdowns if he showed more patience.

In Week 1 last season, Bell had a 29-yard reception against the Vikings, and if he waited for a downfield block from guard Larry Warford, it could’ve gone for longer. In Week 7, Bell was running parallel to Warford and center Dominic Raiola on an 18-yard reception, but his decision to speed ahead and cut inside cost a likely 46-yard touchdown.

Bell was better at setting up his blocks on a 37-yard screen against the Steelers in Week 11 when he waited for Warford, a play that got the Lions to the 2-yard line.

Bell’s strength is his ability to run through tackles, but if he improves at finding the right seams when he reaches the second level, he should be even better in his third full season with the Lions.

Lions training camp position previews

Monday: Defensive backs

Tuesday: Linebackers

Wednesday: Defensive line

Thursday: Offensive line

Friday: Wide receivers and tight ends

Today: Running backs

jkatzenstein@detroitnews.com

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Running backs Joique Bell, left, and Reggie Bush, right, will lead the Lions' ground game again this season. / Detroit News illustration / Daniel Mears photos