The second of eight parts previewing the Eagles’ roster before organized team activities begin on May 21.

Here is the schedule:

Tuesday: Quarterbacks | Wednesday: Running back | Thursday: Wide receiver/tight end | May 13: Offensive line | May 14: Defensive line | May 15: Linebacker

Running backs

Who’s back: We don’t know whether Darren Sproles is inclined to give it one more try as he turns 36 in June, but given the Eagles’ busy offseason at this position, it’s hard to see an attractive role for Sproles, unless there are injuries. Last year’s leading rusher, undrafted rookie Josh Adams (120 carries, 511 yards), might have trouble making the team. Also returning are Super Bowl LII hero Corey Clement, whose status after a knee injury last season remains unclear, the ever-present Wendell Smallwood, and Boston Scott, a running back-returner the coaches liked after the Eagles claimed him from New Orleans’ practice squad last year. Oh, and Donnel Pumphrey!

Who’s new: Former Bears Pro Bowl back Jordan Howard is the guy everyone expects to grab the lead role. He carried 778 times for 3,370 yards in three seasons in Chicago. After that, the Eagles have something they haven’t had since LeSean McCoy in 2009: a rookie running back, Miles Sanders, drafted before the fourth round -- Sanders arrived in the second round, actually, 53rd overall. With the backs the Eagles have returning, there won’t be a lot of pressure on Sanders this season, but if he develops as a receiver and blocker, one would think he has the inside track at the No. 2 spot.

Who’s gone: Jay Ajayi sits in free agent limbo, with his endearingly violent running style and his iffy knees. There has been speculation about the Eagles bringing Ajayi back now that the deadline for counting against the comp pick formula has passed, but really, where would they put him? Ajayi, coming off ACL surgery, won’t be 100 percent until the season starts. That’s probably about when somebody decides they need him, after injuries ravage a roster or two. Other than Ajayi, nobody is gone, except Sproles, who might or might not be REALLY gone. Crowded room, and without any of those “fill out the roster for camp”-type guys. Running backs coach Duce Staley will have a busy spring and summer.

Roster competitions: Figure Howard and Sanders are on the team. Probably Clement, too? After that, it’s who brings the juice in OTAs and (really) training camp, when the pads go on. How many backs do you keep? The answer might have to do with Sanders’ progress. If he carves out a big role, maybe you only keep three, with a fourth on the practice squad. If Sanders ends up being a very limited-role guy as a rookie, you keep four. Have to think if Sproles tosses his helmet into the ring, he’s on the roster somehow. Smallwood, Scott, Pumphrey and even Adams might have an uphill climb to make the 53.