It'll end up on giant screens and promotional posters and videos before they fight. When ring announcers welcome them at the beginning of the fight, and call them out as the winner at the end, it's all part of it.
It's what made Marvin Hagler "Marvelous," Ray Leonard, Ray Robinson and Shane Mosley three lumps of "Sugar" and Muhammad Ali simply "The Greatest." Names are names, but a nickname is a moniker that becomes part of a fighter almost as much as the way they attack in the ring.
It's a descriptor that follows them throughout their career and their lives. Yes, other sports have players with nicknames, but in team sports it can get lost, outside of a few rare exceptions.
But in boxing, where there are only two fighters in the ring, it becomes something more -- especially when it's emblazoned on a fighter's trunks.
"It describes your alter ego," Claressa Shields said. "I think people get confused when they feel like fighters are the same person they are inside the ring as they are outside the ring. A lot of us are completely different."
Nicknames mean different things for everyone and cover a spectrum -- from the ludicrous to the meaningful, to something random that just kind of stuck. They can be used as differentiators for people with common names, and as a way to try and create excitement and brand recognition for fans.
"Money" became a way of life for Floyd Mayweather -- his lifestyle brand is called "The Money Team," or TMT for short. "Golden Boy" enveloped a lot of Oscar De La Hoya's persona, and became the name of his boxing promotions company. "Raging Bull" became more than a nickname for Jake LaMotta -- it turned into a 1980 classic movie nominated for eight Academy Awards and nabbed Robert DeNiro the Oscar for Best Actor.
We spoke to some of today's fighters to understand the origins of their nicknames.
Teofimo Lopez: "The Takeover"
Teofimo Lopez and his sister, Andrea, were sitting at home in Las Vegas in 2017, kicking around ideas. Trying to think of a catchphrase more than a nickname -- something to describe Lopez's lofty career aspirations.
"I think it has a statement or a stamp on it that that is yours," Lopez said about having a nickname. In thinking of fighters like Mayweather and "Iron" Mike Tyson, they were certain that Lopez needed something.
"I was like, 'Let's do 'The Takeover.'' She said, 'We taking over the world,'" Lopez said. "I said, 'Say that again.' And I put 'The.' And she put 'Takeover.' And we just put it together, man."
By 2018, Lopez and his team started really pushing "The Takeover" as a concept, not knowing if it would actually stick. They thought it might, but Lopez put on the full court press as he tried to mention it in every conversation and social media post he could.
By osmosis, it became his nickname -- a transition from "El Brooklyn." He still likes "El Brooklyn," as it ties into where he comes from. Lopez fought as "El Brooklyn" in New York. But as he grew, "The Takeover" made a lot more sense.
It serves a dual purpose. Besides sticking with fans, it sends a message of what he's trying to accomplish.
"When you think of 'Takeover,' it's everything. The world and everything in it," Lopez said. "And that's what it comes to, and that's what I'm trying to imply. Teofimo is not just going to be a name that you only hear once."
Tyson Fury: "The Gypsy King"
The King of the Gypsies is real and, as Tyson Fury tells it, he has lineage on both sides of his family who were once "The Gypsy King": Uriah Burton and Bartley Gorman. They fought bare-knuckle. While Fury does not, he said he earned the title of "The Gypsy King" after beating Wladimir Klitschko in 2015 to win the WBA, IBF and WBO heavyweight titles. And, unlike the titles he did let go for a period of time, he hasn't relinquished the nickname since.
"I always knew I'd become 'The Gypsy King' and that's the ultimate nickname," Fury said. "I always aspired to be the best, always wanted to be the heavyweight champion of the world. And there's a lot of honor and respect that comes with my inherited title because there's gypsies in every country in the world.
"I don't know if you notice, but they always come and support me. Whatever country I go to in the world, there's gypsies there and I am 'The Gypsy King.' So they all come to support me."
Fury said he's declined other awarded British titles of nobility because of his respect for the honor of being "The Gypsy King." And it's a title he doesn't plan on giving it up for a long, long time.
Fury also wants to have the star power of someone bigger than a boxer -- rather that of a crossover star or even a musician, mentioning Elvis and one of his personal favorites, Tom Jones.
Boxing, he says, is merely the beginning of a journey.
"Gypsy King is a badass mother-----," Fury said. "That's what you should know. He's a bad man. He's taking over."
Claressa Shields: "GWOAT"
Claressa Shields finally decided it was time for a change. For years, since she was a kid starting out in boxing, Shields had gone by "T-Rex." It was on her gear. Heck, it was the name of the 2015 documentary made about her life.
But things have changed. She is one of the best, if not the best, female boxer in the world. She won her professional MMA debut with only months of training. So she saw the need for an update.
"GWOAT, Greatest Woman of All Time, goes into like I'm boxing now, I'm two-time undisputed, three-time division world champion," Shields said. "I'm [a] MMA fighter, 1-0 with one knockout. I just felt GWOAT fit me better now because really I can handle any boxing style, any weight class, any sport.
"You got MMA, you got boxing. And I'm just kind of like, great, all around. So I just thought it was time to go ahead and just change it permanently and just let 'T-Rex' go."
Shields said she made the decision on the switch after her fight against Marie Eve Dicaire in March on a pay-per-view card she headlined. The win made her a two-division undisputed champion and a three-division world champion, as well as the first boxer in the four-belt era to hold undisputed championships in two weight classes.
She believes her longtime fans saw the process and had waited for her to make the switch. It's also a nickname she coined and trademarked in 2019 for use on clothing and other gear.
"It's definitely been picking up a whole lot of momentum in the past year," Shields said.
Her now-former nickname, "T-Rex," came from the start of her career when she was age 11 and described her fighting style -- a kid at the time, she was tall and lanky with fairly short arms. So the guy she sparred with called her "T-Rex."'
"He said, 'Because your arms are short and you be looking like a little dinosaur when you trying to get us,'" Shields said. "He kind of did a little T-Rex arms and his mouth open and I just started cracking up."
Childhood laughter led to a realization there was a catchiness to it, turning it into one of the most known nicknames in boxing. Throughout her career, that includes headlining her own pay-per-view card earlier this year, she kept her T-Rex moniker.
But she knew at some point it would be going away. That as her career progressed, she would want something a little different.
While she won't have an issue being connected to "T-Rex," she feels like she's in a situation similar to when Floyd Mayweather switched from "Pretty Boy" to "Money."
"I'll always have 'T-Rex' inside of me," Shields said. "But I just felt like 'The Greatest Woman of All Time' is 'T-Rex' times 10."
Sebastian Fundora: "The Towering Inferno"
It makes sense that the then-20-year-old Sebastian Fundora had never heard of '"The Towering Inferno"' when it was suggested to him as a nickname in 2018.
The 1974 Paul Newman-Steve McQueen film came out 25 years before Fundora was born. But when he signed with promoter Sampson Lewkowicz, there was talk of a nickname.
Fundora is 6-foot-6, so Lewkowicz suggested "The Towering Inferno." Fundora wasn't really looking for a nickname, but four years later, it remains.
"I didn't know what it was," Fundora said. "It was just another nickname for my height. I didn't really care for it that much, but people really started to like it. So if it works, it works."
It was a stroke of ingenuity. Fundora feels his fighting style fits the name, despite still never having seen the movie. He feels his high punch rate makes sense with the moniker that first grew on him when he started fighting on television.
Now one of the rising junior middleweight prospects, he's comfortable with the name and doesn't mind it. "Why," he says, "change a good thing?" So good, in fact, he might even decide to see a movie that's considered one of the better disaster movies of all time.
"That gives me more of a reason to watch it," Fundora said. "No one tells me that. They just tell me that it's an old movie."
Gabriela Fundora: "Sweet Poison"
Freddy Fundora tried to give nicknames to all of his boxing children, other than Sebastian. When he saw his daughter take to boxing, he was struck with an idea: "Sweet Poison," because it fit her personality.
There's a connection to the comic book villain Poison Ivy, and the play-on names went from there.
"Outside of the ring I'm a girly girl and I'm always very feminine," Fundora said. "But then when I go inside the ring, I'm a beast and I'll destroy whoever goes in my way."
The 19-year-old junior bantamweight had initially considered "Twisted Sister," but then decided that would work better on her younger sister instead.
So far, it's worked. The 5-foot-9 Fundora, who turned pro in May, has won her first four fights.
Danielle Perkins: "Skippity Paps"
Perhaps the weirdest nickname in boxing came from videos of a cat. Seriously. Danielle Perkins, a heavyweight who used to play college basketball at St. John's, started saying "Give 'em the Skippity Paps" after watching videos of cats on their hind legs moving their front paws.
Fellow USA boxer Naomi Graham was aware of Perkins' infatuation and called Perkins "Skippity Paps" for the first time. Perkins laughed. So she went with it, even starting to wear t-shirts with cats on them while sparring.
Then she started wearing cat t-shirts for sparring.
"They are all different cats," Perkins said. "When I go to spar. It just keeps it light.
"I do try to break people's jaws when I hit them. The least I can do is show up and be friendly."
Jared Anderson: "The Real Big Baby"
When Jared Anderson was at the Toledo Power gym starting out as a boxer, others would come in, see his size at that time -- almost 6-feet, 200 pounds -- and wonder how old he was. When they were told he was 13 or 14, most people didn't believe it.
Since it was a gym that was as much a boxing training center as it was a place for average humans to try and lose weight or gain mass, they would continually be taken by surprise.
"It's like, 'Wow, this kid is huge, but he's still a baby for real,'" Anderson said. "So it just kind of stuck. They always used to say it. I really didn't like it in the beginning, but it was a good name."
It followed him through his time with Team USA. When he turned pro in 2018, Anderson considered changing it. He even floated out some possibilities on Facebook -- one being the "T-Town Bully." For the quasi-contest on social media, he had different logos made up by a friend's cousin and then let fans decide.
"A lot of my older fans told me the bully wasn't a good look," Anderson said. "Nobody really likes a bully and I understood it and where it was coming from. I kind of liked the name at first, being young-minded, but it's good for promotional reasons and everything.
"Plus, I was never like that, I was never a bully in school or anything, so it's not good to pretend to be something you're not."
And so "Big Baby" still won out. Anderson said he's done shopping for nicknames. It might not be the most original name in the world -- former NBA player Glen Davis and fellow heavyweight Jarrell Miller are nicknamed "Big Baby," too -- but he's "The Real" Big Baby, and it works for him.
Jamel Herring: "Semper Fi"
Herring's nickname is self-explanatory. As a former Marine, it just made sense -- even if at first he didn't care whether or not he had a nickname at all.
"It just fit," Herring said. "'Once a Marine, Always a Marine' is what we go by, and 'Semper Fi' means 'Always Faithful.' I took it as I always stayed faithful to the Corps, always stayed faithful to my craft in boxing.
"So that's why I'll continue to stick with 'Semper Fi' as my nickname."
Herring sees parallels in his time with the Marines -- two deployments to Iraq in 2005 and 2007 -- and his career in boxing. He credits how he mentally handled fighting to his time in the Corps, where he dealt with difficult situations constantly -- enough to have a book written about his life.
He thought about changing his nickname at one point in his career, but then Herring saw it mattered for reasons bigger than himself. When other current and ex-Marines heard the nickname, they knew he was one of them. He found Marines began rooting for him because of it. They felt connected to him.
And even though he's the WBO junior lightweight champion, he prefers "Marine" to "Champ" when people call out to him.
"I don't have to say much. They just know," Herring said. "Sometimes they'll say 'Hey Marine,' before 'Hey, Champ.' That tells you right there, where I came from."
Josh Taylor: "The Tartan Tornado"
Taylor was sparring with experienced pros before his debut and was dominating, so much so that people in the gym started calling him "The Tornado." Taylor liked it, but being Scottish is part of his pride, part of his soul. So he wanted something clearly Scottish in there as well.
"So I said, 'What about 'The Tartan Tornado,'" Taylor said. "And we stuck with that."
While that's the public nickname, there is another one his friends call him with a deeper backstory. Sometimes, Taylor goes by another name: "Hank."
"Hank" is derived from the 2000 Jim Carrey comedy "Me, Myself and Irene," where Carrey played a Rhode Island state trooper with dual personalities -- Charlie Baileygates, and his alter-ego, Hank.
"Hank" doesn't necessarily describe Taylor's personality, but rather a combination of what he does in the ring and some poor decisions with his locks.
"In one sparring and training camp, I went and got a haircut and the barber butchered me and gave me a 'Hank' haircut," Taylor said. "Went back to the gym and was shadowboxing and [former two-division world champion] Carl Frampton came up with 'Hank.'
"It kind of stuck. Sometimes in the gym, I'm hyperactive and a bit crazy sometimes ..."
Taylor prefers to go by "The Tartan Tornado" -- "Hank" is more of an inside joke -- but he doesn't mind it. It suits his boxing style, how he moves and, yes, the haircut he still has to this day.