Jaron Ennis’ quest for a world title has taken him to Atlantic City and Las Vegas. He made his professional debut six years ago in Southern Utah, fought at the Sheet Metal Workers Hall on Columbus Boulevard, and scored knockouts in Flint, Mich. and Broken Arrow, Okla.

Ennis, a 24-year-old undefeated welterweight from Germantown, has fought all over the country in big arenas and tiny rooms. And when he fights on Saturday night in Carson, Calif. with a world-title shot at stake, his biggest fan will be watching from a small town just north of Pittsburgh.

“Jax told me the other day that he’s nervous for the fight because he just wants Jaron to win,” said Missy Ramirez, the mother of 7-year-old Jax Ramirez. “It’s a 7-year-old just hoping that his buddy does well in a fight. It’s a really cute story that I think will last a really long time.”

» READ MORE: Philly’s Jaron ‘Boots’ Ennis could be boxing’s next big star thanks to a family that molded him

Ennis befriended Jax earlier this year after reading a column by The Inquirer’s Helen Ubiñas about Ramirez’s battle with a rare autoimmune disorder called IPEX syndrome and the family’s challenge to find a lifesaving bone marrow match. IPEX syndrome, which affects one in every 1.6 million people, can be fatal if Ramirez is unable to receive a bone marrow transplant.

Ramirez’s father being of Mexican descent has made it challenging to find a match as Be The Match’s Registry has a low percentage of Latino donors. Moved by the story, Ennis wanted to help as he knew his next fight would be just outside of Los Angeles, home to one of the country’s largest Mexican-American populations.

Ennis, nicknamed “Boots,” reached out to the Ramirez family and talks regularly to Jax on FaceTime. Jax’s mother said someone from Ennis’ camp — mostly himself or his father and trainer, Bozy — checks in almost daily.

“We are both definitely fighting,” said Ennis in a video that will air before Saturday’s fight on Showtime. “I’m fighting in the ring, and he’s fighting in a whole different way. At the end of the day, he’s a little kid and he’s going through a lot. I feel he needs someone [to inspire him and cheer him up].”

Jax Ramirez watches video of Ennis’ workouts as the boxer trained in Frankford, finding motivation by watching his friend prepare for his crucial fight. Ramirez is already planning a day for Ennis to visit him as they’ll eat at the boy’s favorite Pittsburgh pizza shop and go rock climbing.

“It’s a beautiful relationship between Boots and Jax,” said Missy Ramirez. “Boots has this huge smile, and he’s so genuine and authentic. Jax just loves talking to him, and they have so much in common despite the distance and any differences. For our family, it’s just really sweet.”

Ennis told Jax that he’s dedicating Saturday night’s fight against former Canadian Olympian Custio Clayton (19-0-1, 12 knockouts) to Ramirez and his fight against IPEX syndrome. Ennis’ father, Bozy, is hoping to have tables at the arena where fans can be swabbed just like they were to see if they can provide a match.

“Boots has given us a gift like no other,” Ramirez said. “We’ve always talked about, ‘I want to elevate this to a level that everyone understands how critically important it is to join the registry.’ Boots is giving us, giving Jax, and giving every patient on that donor registry drive faith and hope for their future. Saying thanks just doesn’t seem good enough.

“I’ve went through almost every emotion today in anticipation of tomorrow. Not only for Boots but for what it will mean to every person on the registry. Boots has the ability to touch the pockets of diversity that haven’t been touched before. That’s what it’s about. There’s not a lot of diversity on the donor drive so kids like Jax don’t get that second chance. Jaron is giving every person of color a chance to be heard and that’s just an incredible thing.”

A win on Saturday will make Ennis (28-0, 26 KOs) the No. 1 contender for the IBF’s welterweight title. He’s pegged by many as not only a future champion but a future superstar of the sport. He can do nearly everything in the ring — fight right-handed or southpaw and box or slug — and has recorded 18 straight wins by stoppage.

His bout on Saturday is his biggest yet as it is the fight that can align him for a world title. And Jax Ramirez will be allowed to stay up late in Western Pennsylvania to watch his friend.

“Jaron is forever a part of our family,” Missy Ramirez said. “What he’s done is to acquire a family in Zelienople, Pa., who will be with him forever. We truly went from fans to family. They’re incredible people doing incredible things.”