(John McDonnell/The Washington Post)

RICHMOND — The play stands out even now, nearly two years removed. Roy Helu turns the corner and hurdles a Seattle defender, sticks the landing and takes off on a long touchdown run.

That 28-yard touchdown run is why Mike Shanahan hopes Helu stays healthy this season. Helu isn’t competing for a starting job — Alfred Morris locked that up with his strong rookie season — but he could fill an important role on third downs. It would be good for Morris to develop into more of a threat in the pass game, but it’s also good for him to have a strong back behind him who can fill his job.

Helu still needs to become a consistent pass protector, but he’s 5-foot-11 and 215 pounds and fast.  Witness the Seattle game, the first of consecutive 100-yard rushing days.

“He made such a big play and it was a difference in us winning that game,” Shanahan said. “He has that type of ability. He’s strong, he’s fast, he’s elusive and he’s healthy now so we have a chance to evaluate him. Hopefully he can keep improving like in his rookie year.”

Helu improved in his rookie year, he also battled knee problems that added to questions about his durability. Then he played in only three games last season because of turf toe — a sprained ligament near the joint of the big toe — and it lingered into the spring. Helu says he feels fine and is more aware of why a certain body part might feel irritated. He said he’s warming up better and doing more post-practice maintenance.

But he’s also feeling more comfortable in the offense. Though he was in the system two years ago, there was a change for the running backs last season operating out of the pistol formation. He wasn’t used to trying to see the defense from directly behind the quarterback.

“Sometimes I have to look around because the [defenders] are stacked in front of the quarterback,” he said. “It’s still something I have to adjust to. Last summer it was hard and this spring it was hard, but right now I’m used to it.”

Helu also said sitting out gave him more time to study the offense as he tried to turn a negative into a positive.

“You get to see a lot more from a different perspective,” he said. “I see a lot more protection and the scheme and why we do certain things. For instance we’d run some plays where I didn’t know what would happen in the secondary with our blocks. Then after seeing it and hearing it all the time on why we run certain things and make adjustments, now I have a feel and I can trust myself and know the blocks.”

Last season, the Redskins ran the triple option at times with various players — Brandon Banks, Josh Morgan, Dez Briscoe. Helu would love to run that this year, but doesn’t want to become that specialized.

“I better be able to do it because it’s a part of our offense,” he said. “I don’t want to put a lid on my container — I want to be a well-rounded back. I want to be excellent across the board, with that being a part of it.”

What’s ahead:

Today’s practices are at 10 a.m. and 3:20 p.m. Here’s our guide to camp, if you’re headed to Richmond.

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D.C. Sports Bog: Fans go to training camp for honeymoon | The Bog & Redskins

John Keim is leaving The Post for ESPN

Observations: Day 4Day 3 | Day 2 | Day 1