Two undrafted players help power the Miami backfield.

MIAMI GARDENS, Fla. — Seated side-by-side on padded tables in the trainer’s room, they began to understand one another, two testaments to resilience.

Raheem Mostert, the halfback, was rehabbing from surgery to repair chipped cartilage in his knee. Alec Ingold, the fullback, was recovering from a torn anterior cruciate ligament. Both had just joined the Miami Dolphins.

Nobody gets to know anybody in a locker room. Players talk as they come and go. They bark and tease. But it’s not the place for deep discussion. In the trainer’s room, however, time moves slowly. The volume is turned down, and honesty is inevitable. Rehab exposes all vulnerabilities, physical and psychological.

“That’s the place where you get down to who the person is,” Ingold said. “Everyone there is getting tested personally and professionally. It’s a different thing when you are on those tables.”

The two undrafted players learned they had much in common. Both had been doubted and dismissed.

And then they came together, creating an uncommon synergy. You can see it on game days now.

“He’s my eyes before I hit a hole, and I just play off him,” Mostert said.

“Our feet move in sync sometimes, and I’m like, how is that even happening in the speed of battle?” Ingold said.

The duo is the primary reason the 9-3 Dolphins possess the topranked rushing game in the N.F.L. Mostert, 31 and in his ninth N.F.L. season, is having a career year. His 16 touchdowns are the secondmost in the league. Ingold was voted a captain by his teammates — he has been a captain on every team since high school — and is the one who speaks last before the team takes the field. Before the season, he signed a three-year, $12.2 million deal, the secondhighest-valued fullback contract in the league.

Still, there are doubts. When Dolphins wide receiver Tyreek Hill was asked about the possibility of winning the most valuable player award, he said, “We have a player on this team that’s better than me. And means more to this team than me. And his name . . . is Alec Ingold.” Smirks and snickers. Mostert heard the talk in the offseason. The Dolphins supposedly were willing to make Jonathan Taylor one of football’s highestpaid running backs. Miami also reportedly called the Las Vegas Raiders to inquire about Josh Jacobs. Dalvin Cook campaigned to join the Dolphins, and interest appeared mutual when Coach Mike McDaniel called him a “great player.”

Mostert and Ingold have been doubted by their own teams, their opponents and football fans. Each knows too much, however, to doubt the other.

After establishing himself as one of the best kick returners in college football over four years at Purdue, Mostert was disappointed when he was not drafted in 2015.

“I remember that feeling, just sitting there on the couch in my apartment with my now-wife and my in-laws, basically just feeling kind of sad,” he said.

He had offers from the Chiefs, Colts, Eagles and Falcons and signed with Philadelphia for a $5,000 bonus. In preseason games, Mostert led the N.F.L. with 348 scrimmage yards and returned five kicks for 162 yards.

He thought he made the team on cutdown day as the Eagles released player after player. But at about 7 p.m., they had one more cut to make. Coach Chip Kelly wanted to see him. When Kelly told him he hoped he cleared waivers so he could be placed on the practice squad, Mostert broke down. Kelly hugged him.

“It was heartbreaking and devastating,” Mostert said. “But at the same time, it helped me build up a callous.”

That callous was useful because more cuts were coming.

When Mostert was at the Eagles’ hotel in Atlanta awaiting the season opener as a practice squad player, Joe Philbin’s Dolphins signed him to their 53-man roster. Four games into the season, Philbin was fired and Mostert was waived.

Mostert was walking up the stairs of the team facility to sign with the practice squad when his agent called. The Ravens were claiming him for their 53-man roster. He walked back down the stairs and caught a flight to Baltimore. After six games, the Ravens told him they were cutting him. He sat out one practice, but before the Ravens submitted the transaction to the league, they changed their mind. Mostert was cut the following week, though, and claimed by the Browns, with whom he finished his rookie season.

Ingold, meanwhile, had scored seven touchdowns his senior season at Wisconsin and was voted the team’s offensive impact player of the year. He was invited to the 2019 N.F.L. combine — the only fullback asked.

For the draft, Ingold hosted a party at his family’s house in Suamico, Wis., to celebrate what they thought would be a lateround selection. The Dolphins had shown the most interest that spring, but in the seventh round they chose another fullback — Chandler Cox.

“When that happened, it stung,” Ingold said.

The Bills, Jets, Raiders, Texans, Titans and Vikings wanted him as a free agent, and the Raiders, long the destination for outcasts, were his choice. He signed for a $10,000 bonus, and though he wasn’t expected to make the team, his enthusiasm and execution earned him a roster spot and a role in Jon Gruden’s offense.

Ingold and Mostert broke out in 2019 playing in the Bay Area. With the 49ers, Mostert led N.F.L. running backs with an average per carry of 5.6 yards. In the N.F.C. championship game against the Packers, he had 29 carries for 220 yards and four touchdowns. Ingold was voted an alternate to the Pro Bowl.

Then knee problems came for both in 2021, followed by another wave of doubts.

After Mostert injured his left knee in the season opener, he said the 49ers wanted him to have arthroscopic surgery and return later that season. Instead, he opted for a more invasive surgery that required him to miss the entire year.

In a November game against Kansas City, Ingold tore his right A.C.L., ending his season. Both almost quit football. After Ingold’s junior season at Wisconsin, he says he became lazy and entitled. He also became benched.

Ingold subsequently started preparing for a life without football. He went to a job fair and interviewed for a position selling computer software. Ingold was told the job was his, but he eventually turned it down and rededicated himself to football.

“I basically just went into this hole of worrying about football 24/7,” he says. “I would go into the facility and spend 15-hour days there.”

In Mostert’s second N.F.L. season, he earned a roster spot at the start of the year for the first time, with the Browns. He and his fiancée, Devon, celebrated with a prime cut of meat at a place they couldn’t previously afford.

Devon was at her bridal shower the following day and Mostert was home basking in his accomplishment when his phone vibrated. Browns General Manager Sashi Brown wanted to see him. Not wanting to ruin the bridal shower, he didn’t share the bad news with Devon until later.

He thought about giving it all up. Devon told him to keep going.

Mostert was cut three more times before signing with the 49ers. That’s where he met McDaniel, who was in charge of the team’s run game, and together they bloomed.

As a free agent, Mostert had opportunities with the Bills, Chiefs and Raiders. The 49ers still had interest, too. But none of them had McDaniel, who was hired in February 2022 as the Dolphins’ head coach.

Mostert, as McDaniel saw it, was the perfect fit for his offense, in part because of his freakish speed. But there was more.

“Raheem has the running style that fits what we’re trying to do in that he is an aggressive, decisive player, naturally presses blocks and finishes downhill on contact, henceforth his career low in yards per carry is 4.9,” McDaniel said. “Beyond that, what comes from his heart is something at the N.F.L. level that you definitely need from a player that you are going to give the ball to like we do in critical situations like Raheem.”

McDaniel’s scheme also was a factor with Ingold, who chose the Dolphins over the Texans and signed on the first day of free agency.

“Alec has the disposition and mind-set like Raheem where he’s trying to attack whatever his job is each and every play with a fearless mind-set,” McDaniel says. “Alec is a unique example of a ballplayer that’s got the skill set of a traditional fullback where he’s able to displace defenders on contact, and he’s also a [receiving] threat and extremely smart player, so he allows us to do a lot of varied presentations of fullback personnel.”

McDaniel recognized something in each that others missed, something he also saw in the mirror.

“I very much relate to someone who was told he can’t,” McDaniel said.

Ingold and Mostert could have been angry about the lost chances. Instead, they are grateful. This explains the joy both bring to the job. Mostert’s smile awakens other smiles. Patio heaters have nothing on Ingold’s warmth.

“Playing a kid’s game for a living, man,” Ingold said.

When the Dolphins’ defense is on the field, Mostert and Ingold sit next to each other on the bench, as they did on those trainer’s tables.

In their resilience, they couldn’t be more alike.

‘He’s my eyes before I hit a hole, and I just play off him.’ RAHEEM MOSTERT, referring to backfield mate Alec Ingold.