MIAMI – Raheem Mostert sat back in his chair, balancing its back legs with his planted feet as waves of reporters from his six previous stops in the NFL peppered the 49ers running back with essentially the same series of questions.

Are you resentful toward the teams that released you?

Did you use the slights as motivation?

What exactly did those teams miss?

“It’s not so much about what they missed … maybe I didn’t do just enough,” Mostert said Wednesday at one point. “I take the blame on most of that stuff because I’m always going to ask myself, ‘Hey, when I was here, what did I do wrong? What could I have done differently?’

“When you’re the underdog most of your life, those are the type of the questions you’re going to ask yourself because you want to be better.”

If Mostert had faulted only the teams that failed to see what the 49ers eventually saw, it’s unlikely he would have persevered. But that doesn’t mean he forgot the feeling of being cast off or didn’t use snub after snub as motivation.

The dates of each of his six releases are listed in order on his iPhone’s Notes app. The first: Sept. 4, 2015. The team: The Eagles. While some Philadelphia fans may harbor ill will toward the Eagles for allowing Mostert to get away – especially after he ran for more than 200 yards in the 49ers’ NFC championship game victory last week – he does not.

“I look back at that one like, ‘Man, they really did give me a gateway to the league and opened it up,’” Mostert said of the Eagles, who signed him as undrafted rookie. “I tried to take advantage of as many opportunities as I could. For me, Philly definitely has more of a spark in my journey because that’s the first [team] I was with.”

Mostert’s sojourn to Super Bowl LIV isn’t wholly original. He grew up impoverished. Around violence. Without suitable parental guidance. But it is his story. And it’s obvious he believes that he wouldn’t have gotten to this stage without the various obstacles he has had to overcome.

Mostert wouldn’t go into much detail this week at the Super Bowl, but his childhood in Daytona Beach and New Smyrna Beach, Fla., as detailed in a recent Bleacher Report article, was far from ideal. One story alone encapsulates those years.

When Mostert was around 4, his stepfather bought a gun after a gang had raided their home. One day, young Raheem found the gun, loaded, and accidentally shot himself in the big toe. He lost a large chunk of that digit and it still looks sawed-off many years later.

He says the gnarly toe has never affected his balance, which is quite remarkable considering the speed which the former track star can reach.

“Never,” Mostert said. “It’s actually my good-luck charm.”

It’s a reminder of an upbringing he would escape through football, surfing, and skateboarding, and eventually, tangibly, when he left for Purdue on scholarship. But he would be hounded by his past when his stepfather shot his 18-year-old stepbrother four times in a domestic dispute on Father’s Day 2014.

Mostert’s brother somehow survived. His stepfather is still jailed. The way Mostert hits gaps in the 49ers’ potent run offense suggests he’s still running from his troubled history. Or maybe he’s just fast and nimble.

“If you run a 10.15 100-meters, and you also have professional surfing ability, you’re good at a lot of different things,” 49ers run game coordinator Mike McDaniel said. “I think he’s benefited from getting more reps at one specific thing. But when you look at Raheem as an individual there’s a ton of things he’s done in his life that a lot of people would find insurmountable.”

Mostert wasn’t a star in college. But the Eagles took a flier on his speed. When he first showed up at spring workouts, wide receiver Jordan Matthews and running back Darren Sproles had been clocked the fastest in practice at 22.7 m.p.h.

“I’m like, ‘Nobody’s touching that,’” said Matthews, now Mostert’s teammate with the 49ers. “Raheem comes and on his second day he hits 23. It was just like, ‘This guy’s got something.’ ”

Mostert wasn’t just a burner. He gained 351 total yards from scrimmage in the preseason. But the Eagles already had established veterans DeMarco Murray, Ryan Mathews, and Sproles. There was one spot available and it was down to Mostert and Kenjon Barner.

“I came in with three backs already on the roster,” Mostert said. “Me and Kenjon were fighting for that fourth spot. So I came in thinking, ‘Look, if I don’t make this team, at least I got guys in front of me I can learn something from.' ”

He didn’t make the team, but the Eagles brought him back on the practice squad two days later. The Dolphins, however, poached him for their 53-man roster a week later, beginning a 15-month stretch in which Mostert spent time with six teams.

He went from the Eagles to the Dolphins to the Ravens to the Browns to the New York Jets to the Bears before finally Chip Kelly, then with the 49ers, brought him to San Francisco. Mostert played in 14 games over that span, but mostly on special teams. He had one rushing attempt.

“I view all of them the same but in different areas of my life,” Mostert said of his six stops. “Some areas were really touching for me. And some areas I was just like, ‘Oh, I went to this city and got to go on Michigan Avenue and eat deep-dish pizza.’ ”

Kelly was fired the following offseason, but it’s not as if new coach Kyle Shanahan immediately inserted Mostert into the offense. It wasn’t until the middle of 2018 that he became a regular in the backfield.

But the 49ers signed Mostert to a three-year, $8.7 million contract last March and he took off in 2019, even though he had to share carries with Tevin Coleman and Matt Breida. He led the team with 772 yards rushing, 5.6 yards per carry, and eight touchdowns on the ground.

Coleman was featured more in the divisional playoff win over the Vikings, but when Coleman left the NFC championship game against the Packers with a shoulder injury, Mostert exploded for 220 yards and four touchdowns on 29 carries.

Shanahan has received as much credit for the 49ers’ success on the ground as any of his players. His zone-blocking scheme, the diversity of his calls, and the way he creates mismatches with presnap motions has certainly benefited the running backs. But Mostert’s vision, as much as his speed, melds with the offense.

“People talk about our scheme a lot, but it’s more our players working together and the conviction that they play with … the effort,” said McDaniel, the run game coordinator. “Raheem has a tremendous group of individuals working to give him space, and I think he does very well when he’s in space.”

Mostert has taken advantage of his opportunity. The married father of a 1-year old son doesn’t want to forget his struggles, both on the field and off, but he said he has no resentment about the rocky path it took to get him here.

“Being here I’m grateful for that. It just took some time,” Mostert said. “I always joke with guys that it took me five years. But like I said, ‘It’s just a journey.’ ”