Simone Biles was already the three-time defending gymnastics world champion when I met her for the first time, in January, at a photo shoot for her signature leotard line, yet everyone in her entourage was wary of talking about her qualification for the Olympics, let alone her anticipated coronation at the Games. “We have to get there first,” Aimee Boorman, her coach, said. “Everybody, collectively, let’s just knock on some wood here.” Boorman joked that she wanted to find a wooden bracelet to wear so that she could touch it anytime she talked about the Olympics. But keeping up the pretense, in the face of Biles’s overwhelming talent, eventually became too difficult. “I don’t say ‘if’ she wins anymore,” Nellie Biles, Simone’s mother, told me when we spoke in April, at the Pacific Rim Championships, in Everett, Washington. “I say ‘when.’ ”

Wins became won on Thursday, when Biles took the individual all-around gold by more than two points—the largest margin of victory in the event since gymnastics switched to a new scoring system, in 2006. Halfway through the competition, Biles briefly trailed the Russian gymnast Aliya Mustafina, a moment of faux-tension. Even then the result wasn’t in doubt: Mustafina’s two best events (vault, uneven bars) were behind her, and two of Biles’s best (beam, floor) were still to come. There were times during the broadcast when it seemed that Biles and her American teammate, Aly Raisman, who easily took silver, seemed more concerned with finding the right television camera to wave at than they did preparing for their next rotation.

Which isn’t to say that Biles wasn’t nervous. When Mustafina took the lead after the second event of the day, it was the first time since 2013 that Biles had been behind during a major international competition, and the cameras caught her sitting quietly on the sidelines, cracking her knuckles. Biles is among the world’s most élite athletes, but she is still nineteen years old, and wracked with many of the insecurities that come with being that age. During the same conversation in which Biles’s mother told me that her daughter’s victory was no longer an “if” but a “when,” she also confided that Simone would never say something like that, in part because she simply didn’t see herself as being in competition with the other gymnasts. “Simone doesn’t compare herself to other athletes, and I think, if she did, she’d have a little bit more confidence,” Nellie said. “If she would say, ‘Well, compared to Mustafina, compared to Larisa’ ”—Iordache, of Romania—“ ‘I was ahead of those girls, and I’ve upgraded since,’ she wouldn’t be a mess before competition, she wouldn’t be the way she is.”

I saw this aspect of Biles’s personality up close. In April, I was having dinner at the Bileses’ home when Simone found out that the Romanian team, a traditional gymnastics powerhouse, had not qualified for the Olympics for the first time since 1972. “Does this mean Larisa doesn’t get to go?” Biles said, referring to Iordache, who took silver and bronze behind Biles at the previous two world championships. “That’s so sad.” Her disappointment was genuine, and I found myself trying to imagine Novak Djokovic being disappointed that Andy Murray was going to have to miss the U.S. Open. “I had to remind her,” Boorman told me later. “ ‘I hope it’s Larisa for Larisa’s sake, but Larisa’s the only person who’s gotten close to beating you.’ ”

Biles had secured a place in gymnastics history well before the Olympics began—no woman before her had ever won three World Championships in a row—and after Thursday she can credibly claim the title of greatest gymnast of all time. But there’s work left to be done. The American gymnasts’ gold on Tuesday in the team final had been essentially a foregone conclusion, and Biles’s individual victory Thursday was more a confirmation than a competition. Things get (slightly) more uncertain in the coming days, when Biles will try to sweep the remaining three individual events and become the first female gymnast to win five gold medals at a single Games. (Biles did not qualify on the uneven bars, where her American teammates Madison Kocian and Gabby Douglas are medal threats.) Barring injury or catastrophe—knock on that bracelet, Aimee—Biles will win gold in the floor exercise on Tuesday. The complications come between now and then in the vault competition, on Sunday, and on the beam, on Monday, for different reasons in each case.

Biles was the top qualifier in the vault by a solid margin, but**,** because the vault requires just a single maneuver, rather than the series demanded by every other apparatus, there’s more of a chance that a competitor manages to play spoiler. A number of gymnasts from lesser gymnastics powers have dedicated themselves exclusively to the vault in the hopes of sneaking onto a podium. Biles’s biggest threat in the event is Hong Un-jong, a North Korean gymnast. Not long after Hong arrived in Rio, grainy training footage emerged of her performing a passable triple-twisting Yurchenko—the current Holy Grail of women’s gymnastics. Biles, who performs a Yurchenko with two and a half twists, known as an Amanar, has landed the triple in practice, but her scores have consistently been high enough that the risk of falling hasn’t been worth trying the more ambitious move in competition. For just that reason, Hong didn’t try the triple in qualifying, but everyone suspects that she will go for it on Sunday in an attempt to best Biles. (Two gymnasts from India and Uzbekistan, meanwhile, will be trying another difficult vault, called a Produnova, which is especially dangerous—when I asked Biles whether she might ever attempt the vault, she told me**,** “I’m not trying to die.”) If Hong lands the triple, the extra difficulty points could be enough to put her on top.

On Monday comes the beam. Biles is the undisputed favorite, but the event is also the sport’s most unpredictable. (To understand why, walk out to the curb and try to spin seven hundred and twenty degrees on one foot, or do a backflip, without falling off.) Even the best gymnasts sometimes fall off the beam, and at last year’s World Championships Biles very nearly did just that. (Watch here, at the forty-five second mark, and realize that the fact that she’s able to stay on at all may be the most athletic thing about the whole routine.) When I asked Biles about the incident, she said that she had stumbled for a shockingly pedestrian reason: the competition was being held in Glasgow, and just before she stepped into the front flip that sent her tumbling, the crowd cheered for a British gymnast who had just finished her floor routine. Biles had been thrown off by the noise. Falling would all but hand the gold to the next best gymnast—possibly her teammate, Laurie Hernandez. The only thing standing between Biles and history might be a particularly raucous Rio crowd.