John Keim is taking a position-by-position look at the Redskins’ roster heading into training camp. He’s reviewed linebackers, the defensive line and offensive line so far. Today, it’s running backs:

Returning starters: RB Alfred Morris, FB Darrel Young

The Redskins could use Roy Helu's ability in the open field, especially in pass situations (The Associated Press) The Redskins could use Roy Helu’s ability in the open field, especially in pass situations (The Associated Press)

Key backups: RB Evan Royster, RB Roy Helu, RB Keiland Williams

Key additions: RB Chris Thompson, RB Jawan Jamison

The rest: FB Eric Kettani, RB Tristan Davis

Decisions: The Redskins kept four backs last season, so if they do the same this year, it could be tough for either of the rookies to make an impact. However: Roy Helu is coming off an injury and Evan Royster is not a third-down back, despite filling that role last season. So there’s an opening for one of the rookies, or Williams, to earn a spot. It also will come down to which position do they keep more players than usual. In the past it’s been wide receiver; this year tight end will be one. If one of the rookies is that good and Helu is healthy, then there’s a case to be made for five running backs. The Redskins need to decide who will be the third-down back, though health will play a big factor in that choice. Young remains firm as the No. 1 fullback.

Burning questions:  1) Will either of the rookies help? Thompson offers excellent burst, which he showed at Florida State. He’d be a good fit in what the Redskins want to do with some triple-option looks or on third downs. However, he’s listed at 5 feet 7 and did not always excel at blitz pickups, nor did he have a lot of experience in that role. But he is elusive. Oh, he’s also coming off a torn anterior cruciate ligament, he broke his back two years ago and he did not practice with the Redskins this spring. It’ll be a lot to expect him to have a big impact early. Jamison picked up blitzes well at Rutgers and has good hands. He’s not speedy, but has the making of an all-around back or even just a third-down back. Jamison did a nice job making defenders miss once past the line. Can he do that in the NFL? In the end, it could be difficult to keep both rookies.

2) What can the Redskins expect from Helu? Clearly we know he’s not the most durable back. That was the knock on him coming out of college and after knee problems in his first season and turf toe in his second, that rap hasn’t diminished. The ironic thing is Helu is the most well-built of the backs. But he’s a necessary weapon because of his speed and ability to make defenders miss on the outside. They don’t need him to carry 15 times a game, but they do need him to be a threat on screens, for example. He could use a little more patience and better vision on some of his runs to set up defenders, even on screens. But his touchdown vs. Seattle two years ago – hopping over a defender at the line – remains one few on this roster would make. So as long as he’s healthy, Helu should play a role. He has improved in protection, enough that it should not be an issue (two years ago he had a bad habit of lowering his head, losing sight of the rusher).

3) What role would Royster play? He’s not a big threat as a third-down back because of his lack of explosiveness. But Royster is a move-the-chains runner who is best served getting 15 or so carries to gain a rhythm. Royster did not always look comfortable running the ball last year because he never received the bulk of the carries. But he’ll still have to be beaten out.

What to watch for: Morris’s encore. Anyone who thinks Morris only benefited from the zone read did not pay attention to his year. Yes, Morris ran the zone read well and was helped by the extra attention paid to Robert Griffin III on those runs. But the play-action passes worked so well because of Morris – ask Kirk Cousins how he benefited in his one start from the way Cleveland defended Morris. The Browns ran right at Morris, leaving them susceptible to play-action and bootlegs. Guess what beat them? And Morris’s skills as a runner should not be overlooked. He’s patient, presses the hole well – getting a yard behind the line – forces the defense to commit, sets up his blockers to seal and then cuts back. He’s a terrific fit in this offense. Morris averaged 4.6 yards per carry on non-zone-read runs – and he averaged less than four zone-read runs per game. He’s a tough runner who unofficially gained 1,000 yards after contact. He’s still not an every-down back (others were better on third downs) and he’s not flashy, but Morris is good.

Have a Redskins question? E-mail Mike Jones at with the subject line “Mailbag question” for him to answer it in The Mailbag.

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