RIO DE JANEIRO — On the night before the floor exercise Olympic final in women’s gymnastics, Aly Raisman banged on Simone Biles’ door at 9:45 p.m. and told her to “keep it down” because Raisman was trying to sleep.

Biles and Raisman recounted the moment Tuesday afternoon, after Biles had won gold and Raisman silver in the floor exercise to cap off another dominating performance by the U.S. women in gymnastics.

“You’re fine,” Biles said she told Raisman after the door knock. “It’s not hibernating time. We always tell Aly you can sleep when you’re dead.”

Biles stayed up awhile longer Monday. And then she was very much alive one more time in Rio Tuesday, winning a fourth Olympic gold medal with another dazzling floor routine. Biles soaring through the air is a fierce kind of poetry, and her leaps will stand as one of the signature moments of these Rio Games.

“It’s amazing,” Raisman said of Biles. “I don’t even consider myself competing against her. She’s just at another level. She’s incredible. I’m in awe.”

That’s the way the women’s gymnastics turned out to be at these Olympics — there was a category for Simone, and there was the non-Simone category for everybody else. The two intersected only once, when on Monday Biles had a bobble on the balance beam and ended up winning only a bronze. Biles won everything else she entered — the team final, the individual all-around final, the vault and, on Tuesday, the floor exercise.

The beam misstep made Biles briefly seem human, but she was back to being otherworldly again Tuesday and making a case as arguably the greatest female gymnast of all time. That’s an argument she would never make personally, though.

“I would never rank myself,” she said. “It’s weird.”

Her floor exercise was 90 seconds of bliss for gymnastics fans, with Biles bouncing and flipping to Brazilian music. Her leaps were so much higher than everyone else’s that even a completely untrained eye like mine could see the difference. Her score of 15.966 was nearly a half-point higher than Raisman (15.5), and both of the Americans were another half-point higher than everyone else.

At 4-foot-8, Biles became one of the giant stars of these Olympics. As the world champion in 2013, 2014 and 2015, she was supposed to do it. And then she did it, as the weight of expectations never waylaid her.

“It’s pretty insane what I’ve accomplished my first Olympics,” Biles said. “It’s definitely rewarding and I’m very proud of myself.”

That Biles stood atop the medal stand so often certainly didn’t surprise her personal coach, Aimee Boorman, who has coached Biles for more than a decade.

“We knew she would be here if those things fell into place,” Boorman said. “It wasn’t like she necessarily had to beat out somebody else on the team. She had to be Simone and she had to be healthy.”

At 19, Biles would be a strong candidate for a second Olympics in Tokyo, when she would be 23. She has not answered that question yet with any certainty, but it sounds likely. After the parties and the gymnastics tour and “just kind of being normal” for awhile, what comes next?

“First we’re going to have some fun and I don’t want to think about it yet,” Biles said. “We all need to have a little bit of a break.”

Boorman said Biles could easily take a year or even two off from gymnastics if she wanted to and then return.

“I think she would be able to if that’s what she chooses to do,” Boorman said. “Because she’s just so talented. Her skills come very naturally.”

USA Gymnastics is full of talented young women. Some of them, like North Carolina’s Ashton Locklear, would have started for any other Olympic team other than the U.S. Locklear instead became a non-competing alternate for this squad, even though if she had been allowed to compete she would have stood a good chance at winning an individual gold medal on the uneven bars.

“I think it’s true to say,” Boorman said, “that we could have fielded two teams here and they would have gone first and second.”

And if the U.S. had been allowed to field a third team?

“Maybe third or fourth,” Boorman said.

That’s how good the U.S. is at women’s gymnastics, and Biles is the star who flips and twirls above all the others. She was the first gymnast to win four golds in a single Olympic Games since 1984, and joined swimmers Missy Franklin (2012) and Katie Ledecky (2016) as the only American women to have won five medals at a specific Games.

Biles gets to sleep now (Raisman will be happy), and eat pizza. And she said she’s looking forward to walking on some red carpets at some awards shows.

But I’ll bet you anything Biles will be back for one more Olympics.

Because when you can fly like that, it’s hard to stay grounded for too long.