Redskins running back Rob Kelley (20) tries to strip the ball from rookie Derrius Guice (29) during a training camp practice. (Jonathan Newton/The Washington Post)

Toward the end of the Redskins’ second day of training camp, running back Martez Carter sat on a cooler about 25 yards from the action during team drills. As his teammates battled for roster spots, he just watched.

Carter said he wasn’t hurting. He just didn’t have a functional shoe. Not long before, the laces on Carter’s left shoe had ripped off. He was moving quickly trying to get out of quarterback Kevin Hogan’s way, and he’s not sure who stepped on his foot. It might have been Hogan, or it could have been himself.

Either way, Carter, who is fighting for a spot on the roster, missed valuable time on the field. But he said that wasn’t a concern.

“At that point, you just take mental reps, so if you get in on that play and Coach calls that same play, you’ll pretty much be schooled on it,” Carter said. “If I don’t know, I ask one of the vets that’s standing on the side.”

Carter, who joined the team in May after finishing his college career at Grambling State, is one of seven running backs on the Redskins’ training camp roster. When the team has to cut down to 53 players, just four or five running backs will get to stay. That turns training camp into a three-week audition for one of those roles.

“It’s pretty intense, but the vets do a great job of not being selfish, and they keep all the running backs in the loop, no matter whose job is on the line,” Carter said. “The vets do a pretty good job of kind of helping us out and making sure we know where we are and making it a fun ride, instead of just being selfish and keeping the game to themselves and not giving guys any pointers.”

Carter sat next to Rob Kelley during OTAs, and then the rookie asked the young veteran — Kelly is 25, which could be considered old relative to many others at the position — if he could take the same spot once training camp began. So now, those two Louisiana natives always sit together in the middle of the running backs room on the left side. Kelley has been like a “sensei,” Carter said.

Kelley, who has been with the Redskins the last two seasons, started seven games in 2017 but missed most of the year with ankle and knee injuries. Chris Thompson, a sixth-year veteran, also returns after fracturing his right fibula last season. The Redskins’ run game ranked 28th in the league in 2017, averaging just 90.5 rushing yards per game. Part of the team’s effort to improve in this area came in the form of drafting LSU’s Derrius Guice in the second round.

“We have so many multitalented guys, guys that step up when their number is called and can do everything,” said Kapri Bibbs, another running back in the mix to earn a spot on the 53-man roster. “That room really is something that you can really feed off of. It makes you hungry. It makes you more competitive.”

The reality of the situation is clear, and the math is simple. These running backs know a few of their peers won’t be with the Redskins in a couple of months. But that’s not for a lack of ability. Bibbs said he thinks this is the best backfield in the league.

“Every single one of the [running backs] on our team should be on an NFL roster this year, and I love that,” Bibbs said. “I love the fact that if one of our guys leaves out of this room, I know I’m going to see him again. I know I’m going to be able to walk across the field and shake his hand because I see the talent and I see the way everybody runs on this team.”

The weight placed on training camp is undeniable, Bibbs said. Every rep is meaningful. If you have a mishap on one play, the next one needs to be solid so the coaches remember that instead.

But this isn’t just about impressing the Redskins’ staff.

“You’re at this training camp for 31 other teams as well,” Bibbs said. “That’s something that you can never forget. If you make plays and you’re doing your thing when your number’s called, other teams are going to see that.”

For instance, when the New York Jets head to Richmond for joint training camp practices, those coaches will be looking on, too. Still, for now, these backs are eying spots on this team, even if it is with a healthy dose of realism.

“They’re all great kids, they all work extremely hard,” Coach Jay Gruden said. “But at the end of the day, it’s going to be about the guy who protects the football, the guy who can protect the quarterback and makes the tough runs, runs after contact, and we’ll let it play out and go from there.”

As for the others, they’ll have to find a home elsewhere.

More Redskins coverage:

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Trent Williams’s knee is feeling ‘okay,’ but he’s still easing into training camp

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