8:16 AM ET

SAN JUAN, Puerto Rico and BROOKLYN, New York — Amanda Serrano and Jake Paul walked through the Sheraton Puerto Rico Hotel and Casino and out the double doors. By now, the boxing champion and YouTube sensation, who have worked together for the past eight months, have spent enough time together they understand one another.

And here, on this 100-mile-long, 35-mile-wide tropical island, their unlikely bond has another connection. Puerto Rico is Serrano’s birthplace and Paul’s adopted home. They both feel close to this place, and on this day, the fighter wants to show her promoter something important.

They walk across the plaza to Distrito T-Mobile, one of the main gathering areas in San Juan, attempting to reach a wall that’s part of the exterior of Arena Medalla, a sports bar in the complex.

It might not seem like a big deal, but the first time Serrano saw it, she was stunned. “Amanda Serrano” was there, written in black against a yellow background, between baseball stars Bernie Williams, Pudge Rodriguez and Jorge Posada. Not far away, the names of Puerto Rican boxing stars Miguel Cotto and Tito Trinidad were in large, block lettering.

Eager as she was to reach the mural, this short journey included its own set of challenges. Being trailed by a camera crew and Paul’s small entourage, the duo was stopped by security at the entrance. The second they’re halted, the swarm of fans arrives. Cellphones pop up as the crowd tries to engage the pair and take a few pictures.

This is commonplace for Paul, the former Disney Channel star-turned-YouTube superstar who has millions of followers on Twitter, TikTok, Instagram and YouTube. Serrano doesn’t have the same celebrity but she’s approached, too, including by one security guard who mouthed her name and slyly took a photo.

They finally arrive and Serrano shows Paul the small piece of the mural that means so much to her on the island which is always on her brain and in her heart.

“From my very first fight, I always went up in that ring with my Puerto Rican flag, because I am truly a proud Boricua, a proud Latina,” Serrano said. “And just to have Puerto Rico backing me up, it means everything.”

As they linger, fans again engage and Paul is in his element. He poses for photos and dances around. The dichotomy between the two is stark. Serrano stands off to the side, happily taking pictures with those who ask. After about 10 minutes, the pair separates as Paul is whisked away by his team to a waiting SUV.

Serrano, her trainer and brother-in-law, Jordan Maldonado, and a small group of visitors head toward the hotel. Serrano doesn’t get far. In Brooklyn, where she lives, Serrano would be mostly anonymous. Here — not quite.

An older man is walking with his family when he sees Serrano crossing the street. He doesn’t want to bother her, but his daughter stops Serrano and asks for photos. It isn’t the crush of fans Paul endured, but these people are the ones who have been following her career for years. They are the ones she can relate to because they watched her pre-Paul.

Serrano and her team moved two weeks of her training camp from close to their home in the Bushwick section of Brooklyn to Puerto Rico for this reason, because of her passion — and comfort — on the island.

“Just to feel the love,” Serrano said. “Feel that Puerto Rican sun.”

This weekend, back in New York, she’ll be in the biggest fight of her career, against undisputed lightweight champion and the No. 1 pound-for-pound fighter in the world, Katie Taylor. They are the first-ever women headliners on a boxing card at Madison Square Garden. She’ll make seven figures for it, a dollar amount Paul and his business partner, Nakisa Bidarian, pushed for from the start of fight negotiations.

It is attention — financial and otherwise — that she has always wanted. Her spot on that wall? She already earned it with titles over seven weight classes even if she fought most of her career unknown to those outside boxing.

NONE OF THIS has been luck for Serrano, whose boxing career began when she responded to an ad in the New York Daily News by signing up for the Golden Gloves when she was 18. Her sister, professional boxer Cindy Serrano, tried to talk her out of it. So did Maldonado, Cindy’s trainer and husband.

Maldonado put Cindy in the ring with her and told her to beat her sister up.

“I didn’t want to do it,” Cindy said. “I was like her mom; I was her protector.”

It had worked years before. Not this time.

Serrano was determined. After the first sparring session, Serrano returned the next day. And the one after that. And the one after that. After the third session, Cindy and Maldonado relented. Serrano was going to do this, once again emulating her older sister.

To say the two are close is understatement. Serrano and her sister still live in the two-story, gray, aluminum-sided home they grew up in with their parents. The main room of the first floor is a shrine to their accomplishments.

A framed Latin Trends magazine cover and story with both sisters is framed on the wall. So is a pink WBO championship belt and a jacket from Amanda’s 2008 Daily News Golden Gloves championship. IBF, WBO and WBC belts sit in a multi-level display case in a corner, next to a framed “Titanic” poster and a blue Firefly guitar. On another wall is an enlarged Body & Style magazine cover with both sisters on the cover.

The sisters sit on a couch, explaining how so much of what has transpired started in this home and in the room they shared together as kids. When Cindy would get up for school in the mornings, Serrano would secretly wake up, too.

“I would just watch her,” Serrano said. “And I guess that made me who I am, like I wanted to be like her. I wanted to …”

“Oh, I didn’t know that,” Cindy said.

“Yeah, I was like, ‘She’s my role model.’ She still is, so I guess that’s what I kept in the back of my head, so when I saw her doing boxing, I guess I wanted to try, I wanted to do it.”

Cindy became her inspiration. Serrano learned how to brush her hair watching Cindy and how not to use an iron, too, because once she burned Cindy’s clothes trying to figure it out.

“She was always following Cindy around,” their brother, Danny Serrano, said. “And it was great.”

More than Puerto Rico, more than even a boxing ring or a training gym, this is where Serrano is most comfortable. In this house, where she has spent the majority of her 33 years. When she fights in New York, she prefers to stay at home throughout fight week instead of staying in a hotel.

THIS IS ALL different for Serrano. Most of the past year has been. She’s received more attention and done more interviews in the lead-up to her fight against Taylor on April 30 than at any point in her career.

The partnership with Paul has reaped dividends. She said three of the highest paydays of her career have come either working with Paul or fighting on his undercards, including Saturday’s fight, which is more than double she made for any other fight in her career. She has gained broader notice from a different segment of fans — Paul supporters and those on social media. In less than a year, according to Speakrj.com, her Instagram following jumped from 80,000 followers to nearly 350,000 and she gained nearly 10,000 Twitter followers, too. Last week, she became the first boxer to sign a sports gambling partnership with FanDuel.

She knows she’s closer to the end than when she started as an unknown. She said she thinks she might fight for another 18 months and has already begun her second career as a manager. Even then, her plan doesn’t stray too much from her heritage. Her first client is Puerto Rican-born fighter Nicole Ocasio. She plans on having a home in Puerto Rico in retirement and aims to become an influence on the island that has always been a big part of her.

“Just being Puerto Rican is, I don’t know if it’s in the blood to have a big heart,” Serrano said. “We have such a small island, but we have big, big champions coming out of there. It’s amazing.”

WATCHING SERRANO IN Brooklyn and Puerto Rico, it’s tough to picture this thin, muscular, 5-foot-5 woman as one of the hardest hitters in boxing, as someone who disfigured the face of her last opponent, Miriam Gutierrez.

Her power is one of her biggest assets, as is her ability to just keep coming at an opponent — perhaps part of the heart of a Puerto Rican fighter she talks about. Outside of the ring, she doesn’t seem like this.

But there’s a flip that happens as she walks to the ring. Cindy sees it in her eyes.

“I’m like, ‘Oh, she’s ready. She’s ready,’ ” Cindy said. “And she just blossoms from there. She takes over. She takes control.”

When she was an amateur, Serrano said Maldonado used to tell her to “Go Waterboy on him or her,” after the Adam Sandler football movie, because of how she went from docile to enraged and how she hit with power but not refinement.

Her career has been a Hall of Fame one. Titles in seven divisions — only Manny Pacquiao, with eight, has more, male or female. She has 30 career knockouts, more than any of her contemporaries and, according to ESPN Stats & Information research, second to only Christy Martin’s 32 knockouts among women boxers all time. She hasn’t lost a fight in 10 years.

Since she’s been a teenager, her focus has been to reach the point she is now, being one of the best fighters in the world in the biggest fight in women’s boxing history. Madison Square Garden is just a few miles from her home, but before the buildup for this fight, she said she had never been in the main arena — the home of her brother Danny’s beloved New York Knicks — in her life.

When Amanda first walked in, she couldn’t believe it. The Puerto Rican girl from Brooklyn about to be the big deal, to headline in the place of Willis Reed and Patrick Ewing. Of Muhammad Ali and Joe Frazier and her own countrymen, Miguel Cotto and Felix Trinidad.

Serrano’s legacy as one of the best women boxers ever is already clear. Beating Taylor, and doing it in MSG, would give her a win that would be talked about forever — just like those Puerto Rican fighters she grew up admiring in her Brooklyn home when boxing was just an unknown, unexpected dream.

“People knew, ‘Wow, these guys made it, they went to the Garden,'” Maldonado said. “That’s a big thing, and they kind of lost that when these guys retired. They’re looking for the next Miguel Cotto. They’re looking for the next Felix Trinidad.

“Then to be able to give them that through a woman, Amanda Serrano.”