Alfred Morris is the clear starter, but questions remain about the Redskins’ depth at running back. (Nick Wass/Associated Press)

The Redskins found their answer at running back last season when sixth-round pick Alfred Morris went from afterthought to second-leading rusher in the NFL. But questions remain about the team’s depth at running back.

Last season,  Washington released slowly-recovering veteran back Tim Hightower (ACL), and went with second-year backs Evan Royster and Roy Helu Jr. as Morris’s backups.

But Helu lasted only three games before he was placed on injured reserve with toe and Achilles’ tendon injuries, and Royster had an uneven year as Morris’s backup and the primary third-down back.

While Morris excelled at running the ball, Redskins coaches used him only sparingly on third downs until late in the season, when Shanahan gave him the green light to remain on the field as much as he wanted.

As effective as Morris is, the Redskins likely could benefit from a change-of-pace back to spell him here and there, and on third downs. Morris carried the ball 335 times last season – third most in the NFL. At that pace, his longevity could be at risk.

Although Washington’s offense experienced new life last season and ranked among the league leaders following the arrivals of Robert Griffin III, Morris and Pierre Garcon, it could’ve been even better.

As offensive coordinator Kyle Shanahan works this offseason to make his offense even more explosive, he no doubt will look at the running back position. The Redskins lacked a legitimate receiving threat out of the backfield last season. Such a weapon could help,  particularly on third downs. The Redskins ranked 27th in the league (35.8 percent success rate) on third down conversions.

A healthy Helu, who ran a 4.4 40-yard dash at the 2011 combine, could help. Royster, who clocked a 4.65 40-yard dash, is a smooth runner with good vision, but he lacks the explosiveness to be that change-of-pace guy.

As a rookie, Helu recorded 49 catches (third on the team) for 379 yards (fourth) and a touchdown. But the main question about him is whether he can stay healthy.

By the time the 2012 season ended and the Redskins were cleaning out their lockers, Helu still had yet to heal. He said “sprained ligaments and capsules” in his big toes still prevented him from running. Helu said he could jog at that point, but that occasional shooting pain slowed him. He expected to be back to 100 percent by the time OTAs roll around in May. But that remains to be seen.

Will the Redskins look to free agency or the later rounds of the draft to find a speedy back to add to the mix?

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