Tori Nelson sits in a plastic folding chair under an enormous “Happy Birthday” banner in a party room inside a sports complex in Sterling, Va. It’s not Nelson’s birthday, nor is she especially happy. This is her first fight after back-to-back losses that ended an eight-year undefeated streak of 17 wins, including 11 world championship titles, and three draws. She’s 41 years old and has been talking for a while about retirement. And now, just 20 minutes before she is headed into the ring, her broad hands are still unwrapped.

Nelson always has the same man — her manager, James “Ponytail” Hogan — wrap her hands before a fight. Since he’s working the door this night in August 2018, she was expecting her longtime coach, Craig Fladager, the man she calls “Daddy” or “Daddy-o,” to wrap her hands. But he’s in the ring with another fighter and can’t come up.

Outside the ring, Nelson is, in the words of her friend and fellow boxer Tyrieshia Douglas, “a nice churchy lady.” She spends half an hour each day reading and discussing Bible verses with her longtime boyfriend. She’s a hugger, a baby nuzzler, a bestower of silly nicknames. Then she enters the ring and something terrifying emerges, something that won’t let her stop punching until she has annihilated the person in the opposite corner.

Nelson doesn’t totally understand how this change occurs. But she knows it begins when her hands get wrapped — a process that, she told me, feels like putting on a different body.

Tonight, that task falls to Nelson’s assistant coach, Pete Woodson, who has never wrapped her hands before. He’s nervous, his round pale face already sweating as he begins to twirl gauze into small bundles to protect Nelson’s knuckles under her gloves. Their cutman stands behind Nelson rubbing Vaseline into her shoulders, shining up the “Sho-Nuff Nelson” tattoo on her sturdy right biceps. (Nelson’s nickname was dreamed up by Fladager in homage to a character named Sho’nuff from the cult martial arts movie “The Last Dragon.”)

Nelson dances to her music beside her daughter, Simone, 19.

Although she’s clearly upset about having her ritual disrupted, Nelson works to stay calm. Her face glows from her warm-up. Her hair is in a tight French braid. She’s wearing baggy black shorts and headphones, listening to her favorite gospel songs. “My name is victory,” she sings along. As Woodson finishes with minutes to go, Nelson goes silent and lets her heavy-lidded eyes fall shut. Fladager has come upstairs from the ring, and he and Woodson tie up her gloves while someone wraps her in a black satin hooded coat.

Earlier, a group of Nelson’s friends had unzipped a large black roller suitcase that contained Nelson’s 11 championship belts neatly coiled together. Everyone took cellphone photos. “You know you got it when you got a rollie bag for your belts,” one man said.

When it is time to head to the ring, Nelson’s friends stand in front of her, holding the belts as they line up in a supply closet that leads to the basketball court, which has been transformed into a boxing arena for the night. Nelson stands at the back under shelves of bleach and paper towels, hood covering her face, just behind Fladager. Fladager gives someone a thumbs-up, the doors open, and everyone marches into the arena, pink smoke swirling around their legs. Nelson’s fight song, Mary Mary’s “God in Me,” blares over the loudspeakers, and her entourage parades the belts around the ring, in front of a crowd of about 100 people. Nelson jogs in place in her corner and shoots her gloves to the sky.

Nelson is heavily favored to win tonight against her opponent, Tiffany Woodard, a scrappy North Carolina fighter coming off a string of losses. And yet there’s more at stake than usual. If Nelson loses again or even underperforms after her two losses, they would take on a new solidity, possibly forcing her out of the sport altogether.

It goes without saying that there are very few boxers in their 40s. Nelson’s two grown kids and her mother think she should retire. Her boyfriend wants her to move to Florida with him and hang out on the beach. But Nelson seems temperamentally incapable of quitting. What has made her a great boxer her whole career is that no matter who she’s fighting, no matter how much bigger or stronger or more technically acute her opponent is, Nelson always keeps coming. “Tori, when she get in the ring … she gives no f—s,” her friend Douglas told me. “You can hit her 10 … times and she still will come toward you. It’s like she fighting the devil.” Now Nelson and the people around her are beginning to ask: When you’ve been fighting the devil for so long, how do you stop?

Nelson waits as her coaches put on her gloves before a match in December.

Tori Nelson’s boxing career was almost improbable from the start. In 2007, looking to lose weight after her two pregnancies, she joined LA Boxing in Ashburn, Va. On her first day, she met Fladager, a whippet-thin, drawl-voiced former amateur boxer who then owned the franchise. He didn’t think much of Nelson’s physical prowess. “She was just a ham-and-egger like everyone else,” he told me, referring to her less-than-fit physique at the time. But once he saw her spar, he changed his mind. The other fighter was more skilled, but Nelson “came at her with a force and a fury and just beat [her opponent] around the ring,” Fladager recalls. For Nelson, a stay-at-home mom and former homecoming queen who occasionally took minimum-wage jobs to help support her family, discovering this ability felt like a quasi-religious revelation, both random and yet destined by God. “You get into it by accident, you just end up there, and then all of a sudden, this is what you made to do,” she says. “You find out your purpose.”

Nelson had to train a body that had been mostly sedentary since her high school basketball days. The best thing she had going for her in the beginning was sheer aggression: She was a come-forward fighter, swarming her opponent until the other woman got nervous and made a mistake. She won regional Golden Gloves tournaments — competitions for amateur boxers fought for prestige but not money — and then went pro in 2010, fighting for prize money and titles from the various sanctioning bodies.

The early years were tough. Fladager lost the gym, went bankrupt and got divorced, all right around the first year of Nelson’s pro career. He and Nelson trained in his best friend’s garage, clearing away a kayak and sawhorse to make space every day. Nelson was working three part-time jobs: getting up at 6, driving a Loudoun County school bus, training on her break, serving lunch in school cafeterias and working nights at IHOP until midnight or 1 before getting up at 6 again the next day. Her kids, daughter Simone and son Q, now 19 and 22, respectively, spent most of their free time in the gym, getting homework help from what Nelson calls her “family” of other young boxers and trainers. Her husband didn’t like having to go to the gym to see his family. As she remembers it, he told her, “You love boxing more than you love me.” She thought about it and realized she probably did. They divorced in 2014.

You can hit her 10 ... times and she still will come toward you. It’s like she fighting the devil.

Nelson’s career coincided with a boom time for female boxers. In the 1990s, fighters like Christy Martin and Mia St. John were often marketed as a sideshow, wearing scanty costumes. Today, amateur organizations offer female boxers career avenues that didn’t exist 20 years ago. The 2012 Olympic Games were the first to officially include female boxers, and, in 2016, Flint, Mich.-born Claressa Shields became the first American boxer to win gold in two Olympics. Female boxers now appear on Showtime and HBO — not on the undercard of male fights, the way Martin fought under Mike Tyson in the ’90s, but as the main event.

But women still earn a fraction of what men do. In 2011, Nelson won her first title fight, battling Lorissa Rivas for the World Boxing Council female middleweight title. (The different sanctioning bodies have a range of prestige and legitimacy; the WBC is historically one of the more elite.) And yet, without sponsorship or big-money televised fights, Nelson kept her day jobs, and Fladager financed her fights out of his earnings as an electrician. Things shifted in 2013, when promoter James Hogan began lining up higher-profile matches for her, including Mia St. John, then 46. Nelson knocked out St. John in the second round.

Nelson’s 11 world championship belts sit in a suitcase at the Dulles Sportsplex in August. Nelson warms up before her fight in August.

Nelson’s 11 world championship belts sit in a suitcase at the Dulles Sportsplex in August. Nelson warms up before her fight in August.

Nelson’s boxing style evolved as she moved through her 30s. She’s calmer than she used to be, she told me, more economical, more focused on the head game. Nelson’s “not really fast, she’s not a one-punch-knockout-type fighter,” Fladager says. “But she can go into the ring nine times out of 10 and break an opponent down and figure out what she has to do to beat them.” Alicia Napoleon was larger and more athletic than Nelson when they fought over super middleweight title belts in 2016. But over 10 rounds, Nelson hammered at her both physically and mentally: trash talking in the ring, landing powerful hits early on to put Napoleon on the defensive, and finally winning by unanimous decision. The fight remains Napoleon’s only loss.

It was a big win for Nelson, yet it was her only fight of 2016, and she fought just once the year after. Fladager and Hogan were Nelson’s only regular sponsors at that point. If they hosted a bout locally, that meant covering a number of costs: her opponents’ travel and hotels, travel and hotel for the undercard fights, food, state boxing officials, concessions, police, ambulance — all adding up to as much as $40,000 per fight. Nelson has always had a strong local fan base, but ticket sales never totally recouped their losses. Fladager estimates that over the past decade, he has spent about $100,000 on Nelson. Nelson, meanwhile, was supporting her son, who lives with her, and paying tuition for her daughter, who will be the first in her family to get a college degree.

As Nelson started to think about retiring in 2017, she and her team focused on earning some money on her way out. According to Gary “Digital” Williams, a longtime chronicler of Washington-area boxing, a man with Nelson’s number of championship fights would not have these worries. “She’d be set for life, there’s no question about that,” he says. Shields told me, “Right now, I don’t think there’s any woman that can retire from boxing. I can’t retire either.”

Nelson and son Q at First Baptist Church of Sterling in Virginia. Nelson’s friend and fellow boxer Tyrieshia Douglas says Nelson is “a nice churchy lady.”

In 2017, Fladager got a call from Showtime inviting Nelson to fight Shields, who had gone pro in 2016. It seemed like a good way for Nelson to go out: solidifying her reputation while building a financial cushion. In the lead-up to the January 2018 fight in Verona, N.Y., Shields and Nelson somewhat dutifully trash talked each other in the press. Shields told a Detroit interviewer that Nelson, who is about 20 years her senior, “reminds me of my grandma”; Nelson replied in an ESPN profile, “Claressa is going to get that booty spanked by a grandma.” (Nelson is not actually a grandma, though her children are about the age she was when she had them.) It was the most media attention Nelson has ever gotten, and the fight was her most lucrative: She earned $30,000, taking home about $19,000 after expenses.

She was an underdog, expected to lose to Shields. Nelson, however, never fights to lose. Shields was larger than her, more powerful, faster. She landed punch after punch, battering Nelson in the body and face and nearly toppling her in the seventh round; but Nelson kept coming, driving at Shields, searching for the knockout until the final bell. Shields won by unanimous decision.

“Her punches wasn’t hurting me,” Nelson said later. “She hasn’t gotten that grown-woman power yet.” Nelson claims she didn’t have a mark on her the next day. Still, her undefeated record was busted, and her ego was bruised. “I didn’t know how to take it,” she told me. “I went MIA for a while.” She hid out with her mother, who had been sick. She ignored Fladager’s calls. She and I talked for the first time two weeks after that fight, and she was insistent that she would retire by the end of 2018. “These girls are getting younger and younger,” she said.

Nelson does strength training at UFC Gym in Herndon, Va., in July. Nelson’s coach Craig Fladager applies Vaseline to her face before she fights.

Nelson does strength training at UFC Gym in Herndon, Va., in July. Nelson’s coach Craig Fladager applies Vaseline to her face before she fights.

When Fladager finally reached Nelson, he talked her back off the ledge. There was no shame in losing to Shields, one of the greatest boxers of her time. And in fact, Shields had knocked out two of the four women she’d fought professionally before Nelson, while Nelson went the distance. The two women became friends “instantly after the fight,” Shields told me, and now text each other regularly. Shields calls Nelson “O.G.,” short for “original gangster.”

In June, Showtime asked Nelson to return as the opponent for German middleweight champion Christina Hammer, 27, creating tension for a potential Hammer-Shields showdown. Nelson, who was a natural welterweight, had gone up three weight classes by the time she fought Shields, a super middleweight. She fought Hammer in Detroit as a middleweight, and felt painfully heavy. In the ring, it was, she recalls, like “fighting in sand.” Hammer is a natural middleweight, 5-foot-11 to Nelson’s 5-6, with speedy legs and a long reach. She didn’t knock Nelson out, as she’d boasted beforehand she would — she’s had 10 knockouts — but she kept Nelson running and smacked her over and over with a far-reaching left jab. Hammer won by unanimous decision after 10 rounds.

For this fight, Nelson earned $20,000, but she was frustrated afterward. Whereas the loss to Shields had been understandable, she felt she should’ve beaten Hammer. But when we talked after the fight, she sounded more ambivalent about when she might retire. “Next year,” she told me, vaguely. “I’m sure next year will probably be my last.”

Fladager recalled telling Nelson after the Hammer fight, “If you continue to fight out of your weight class and chase money, you’re never going to win.” Now, all Nelson wanted was to start winning again.

Nelson fights Sanna Turunen in December.

After the first-round bell at the fight in August, Nelson’s opponent, Tiffany Woodard, comes on aggressive, throwing big punches that sometimes send her lurching across the ring. Nelson stays on the defensive through the early rounds: ducking punches, gloves up and feet moving in a shambling, sideways gait. By the third round, Nelson lands more punches, driving Woodard against the ropes. Woodard staggers around, furious.

In the sixth round, Woodard lowers her gloves and lets out a sort of war whoop right in Nelson’s face. Goaded past patience, Nelson punches Woodard in the kidneys and throws a whirring left hook to Woodard’s jaw that leaves her legless. Then Nelson unleashes a barrage of hits, pummeling Woodard until she collapses against the ropes — the first time Woodard has ever been knocked out, and the third knockout of Nelson’s career. Nelson roars at Woodard, then stalks back into her corner. A minute later, she’s back to being friendly Tori, grinning and hugging what seems like half of the arena, including a little blond girl who poses for a photo with Nelson, flexing her tiny biceps. A reporter asks when Nelson might retire. “Getting to be time,” she says, shrugging. But her smile is giddy, triumphant.

A few weeks later, I visit Nelson during her shift at an IHOP in Ashburn. Nelson is a fantastic waitress. In heart-shaped earrings and a neatly fitted uniform that covers her tattoos, she buzzes through her section, greeting regulars with a hug, balancing four plates on her arms and, at one point, singing the IHOP “Happy Birthday” song to a family at a table behind me. “It’s pretty awesome,” one of her regulars says, laughing, when I ask what it is like to be served breakfast by a world champion.

Nelson seems relieved after the fight with Woodard. She is dropping weight and feels like she’s gotten her body back. A plan for a third Showtime fight on the undercard of the Shields-Hammer faceoff has just fallen through, at least temporarily, after Christina Hammer postponed the fight for medical reasons. But Nelson keeps training, staying in shape for whoever might want to fight her next. “February, March,” she says, “if I don’t have anything by then, I’m done.”

Over the next few weeks, Nelson’s team starts negotiating a fight against Raquel Miller on the undercard of a Dec. 1 fight between male boxers Deontay Wilder and Tyson Fury in Los Angeles. But that falls through as well. Nelson begins to sound as if she might be mentally easing herself out of boxing. She talks about focusing more on charity work, maybe starting a business.

If Tori didn’t fight, she wouldn’t know what to do. ... If her legs can carry her into the ring, she going to be fighting.

Then, in late November, a fight lands in her lap. The promoters of a local fight night are looking for a main-event boxer who can fill seats. Nelson agrees. Her opponent is Finnish middleweight Sanna Turunen, 43. Turunen is not a significant opponent, and Nelson is paid only a few thousand dollars. And yet, Nelson is exactly as focused, exactly as serious, as she’d been fighting Woodard, Shields and Hammer.

The event takes place at Washington’s new Entertainment and Sports Arena on the grounds of the old St. Elizabeths Hospital, its abandoned buildings looking like the set of a Victorian-goth horror film. Before the fight, the promoters stick Nelson and her team in a ground-floor men’s changing room with lockers and a toilet that keeps randomly flushing. Everyone sits in plastic chairs and banters with the comfort of people used to spending many hours together doing nothing.

I ask Fladager what their plan for the next few months is. He and Nelson, he tells me, are aiming to fight Cecilia Braekhus, the Norwegian female welterweight world champion. First, they’ll need to line up fights with other welterweights to get Nelson ranked by one of the sanctioning bodies and force Braekhus to fight her to defend her belts. The plan would keep Nelson fighting well into 2019 and possibly longer. As Nelson chats with Hogan a few feet away, Fladager lowers his voice. “She’s 42, Tori, so we’re taking everything fight by fight, year by year,” he says. “As of right now, she’s good. But I mean, how much longer? … You just fight until you can’t.” Then he goes back to joking with the others, slapping his thighs and chortling after Pete Woodson accidentally drops a half-peeled mango into the trash and leaps halfway in to recover it.

Hogan begins to wrap Nelson’s hands. She stops joking and falls completely still. Later, she leads the team in prayer. Everyone huddles with their arms around one another and their heads close.

As Nelson receives a final coating of Vaseline from her coaches (“I’ll go home and Noxzema,” she says), Hogan starts yawning. It’s after 10 p.m., and he’s been up since 4 a.m. Apropos of nothing, he starts talking in a rambling, friendly way about Nelson. “If Tori didn’t fight, she wouldn’t know what to do,” he says. “She can’t do nothing else. She wouldn’t be right. … Tori going to be about 60 and trying to get into the ring. If her legs can carry her into the ring, she going to be fighting.”

“Like Mia St. John,” Fladager says. Without responding, Hogan keeps going. “Tori been retiring for 10 years now. ‘This the last one!’ ‘Oh, they got a fight, let’s go.’ Every time! … She can’t stop; it’s in her. She live to fight.” Nelson ignores him and bites down on her mouthpiece, ready to go. Later that night, she wins a unanimous decision in 10 rounds.

Britt Peterson is a writer in Washington.