If Notre Dame red-shirt sophomore Jafar Armstrong and red-shirt junior Tony Jones Jr. stay healthy all season and productively divvy up the rushing attempts and pass receptions out of the backfield, the ever-present pre-season goal of playing several more running backs could fall by the wayside.

Two factors will play into that scenario for Notre Dame in 2019. Armstrong and Jones haven’t been able to stay healthy, and offensive coordinator Chip Long knows there’s a better chance of keeping Armstrong and Jones healthy if some combination of Jahmir Smith, C'Bo Flemister and Kyren Williams can offer the productivity to avoid overburdening the two running backs with virtually all of the playing time.

Backfield by committee? Sure, unless a) a star emerges and b) the three youngsters can’t do all the things necessary to play winning football to effectively spell Armstrong and Jones.

“Each year is so different,” said Long, now in his third year as Notre Dame’s offensive coordinator. “What will we be good at in fall camp? That’s how I start adjusting. I have an idea coming out of spring ball where we could be.

“But it’s still pushing the depth so we can play more guys. That’s the biggest thing this year: getting more guys out there. But you’ve got to show toughness and you can’t be careless. We’re not going to put guys out there that are careless and cause us to lose a game.”

Long is confident Armstrong can do the job, provided he can stay healthy. With Dexter Williams sidelined the first four games of ’18 due to university suspension, Armstrong hit the ground running in his transition from receiver in ’17 when he preserved a year of eligibility.

Armstrong scored two of Notre Dame’s three touchdowns in the season-opening victory over Michigan. Through four games he had 245 yards rushing on 47 attempts (5.2-yard average) and five touchdowns.

Just as Dexter Williams was about to rejoin the active list in game five against Stanford, Armstrong was sidelined with a knee infection, prompting him to miss the game against the Cardinal, followed by the Virginia Tech and Pittsburgh games.

Armstrong returned after that, but Williams had established himself as a dynamic presence in the backfield. Armstrong carried just 28 times for 138 yards over the final six games of the season, although he would add two more rushing scores for seven on the season while continuing to impact the passing attack with 14 catches for 159 yards on the year, including five for 64 against Navy.

“I love him,” said Long of Armstrong’s all-in commitment to becoming great. “With Jafar, he’ll get going so fast…He’s got to keep being detailed in what he does.

“He’ll just go, which you love, but that’s the biggest aspect he has to deal with. That comes with playing a totally new position. You could see him in the spring getting more and more confident. Seeing things a little clearer. But he must tend to the details.”

The maturation of Jones showed itself in the spring after a second straight season marred at times by ankle injuries. Jones ultimately finished with 11 more carries and nine more yards than Armstrong. But it was in the spring that Jones really moved the needle for Long.

“I was really happy with Tony this spring,” Long said. “He was very consistent, which was not the case his first two years. He had a great demeanor each and every day. He wasn’t too high or too low. He wasn’t silly or squirrelly in practice like he had been. He was as focused as I’ve seen him.”

While Jones does not have the speed dimension of Dexter Williams or Armstrong, he is versatile and continuing to improve his ability to run with power. It was Jones’ 51-yard swing pass for a touchdown in the fourth quarter of the USC game that sealed Notre Dame’s undefeated regular season and a spot in the four-team College Football Playoff.

And yet Long wants to see more of red-shirt freshman running backs Jahmir Smith and C’Bo Flemister, and early-entry freshman Kyren Williams. It would create a healthier situation – physically, mentally and emotionally.

“That was very real,” said Long of Smith’s eight-carry, 56-yard, two-touchdown performance in the Blue-Gold Game. “I was really proud of both him and C’Bo with the way they came out during the spring. They both started catching the ball better. Their pass protection got extremely better.

“Jahmir has such a knack for short-yardage, goal line…He’s a natural running back. Him and C’Bo and Tony have played it their whole careers, so they know when to get skinny, when to get big and I really like that from Jahmir. He did it last year when he played in games. The first guy didn’t bring him down, which is great.”

Complicating things – in a good way – is the small-but-mighty Williams, who spent virtually no time carrying himself like the green early-entry freshman he was this spring.

“He acts like an upperclassman and he works like an upperclassman,” said Long of Williams.

So whether it’s Armstrong fully maximizing his potential and developing into a big-time running back, Jones joining him to form a one-two punch, or one, two or three more running backs contributing to the cause this fall remains a great unknown less than three weeks before the start of August practice.

A blueprint to emulate would be that of 2018 national champion Clemson, who featured Travis Etienne (204 carries, 1,658 yards, 24 touchdowns), supplemented by Tavien Feaster (78 carries), Adam Choice (77) and Lyn-J Dixon (62), who combined for another 1,535 yards.

Notre Dame’s running backs don’t have that kind of productivity potential. But a similar distribution of duties would serve the Irish well.

“It reminds me of my first year here at receiver when Miles (Boykin) didn’t play a lot, but kept grinding away and made an impact in the (Citrus) bowl game,” Long said. “Chris (Finke) kept grinding and did the same thing. By the time the bowl game came around, they played 60 snaps and helped us win a game.

“If (the younger running backs) can consistently do that, yeah, we’re going to play them.”