One vault, and Simone Biles' night ended.

The final U.S. gymnast to compete during the first rotation in Tuesday's Olympic women's team finals, Biles opened early on an Amanar and seemed to lose where she was in the air. The best vaulter in the world landed low on what became a Yurchenko 1½ (instead of 2½) and took a massive step forward.

Afterward, she sat with the team doctor, surrounded by her teammates, and shook her head. "I'm fine," she said multiple times before leaving the arena.

If Biles is known for anything, it is her technical superiority and air awareness. What happened on vault was incredibly out of character, but Biles would know better than anyone else that her misfire was more than a fluke. Her routines are so difficult and the skills she performs so dangerous that had she continued to compete with her mindset shaken, she risked catastrophic injury.

"You have to be there 100%," Biles told reporters after the meet. "If not, you get hurt. Today has been really stressful. I was shaking. I couldn't nap. I have never felt like this going into a competition, and I tried to go out and have fun. But once I came out, I was like, 'No. My mental is not there.'"

When she returned to the competition floor, Biles informed her teammates she had withdrawn from the meet. Then she took off her grips, put on her warm-ups and became Team USA's biggest cheerleader. She hugged and offered help from the sideline. She mirrored her teammates' routines as they competed on floor and ran the chalk box to them between turns on bars.

During the meet, NBC reported Biles' reason for scratching was "a mental issue she is having" and added it was "not injury-related." USA Gymnastics followed the report and tweeted, "Simone Biles has withdrawn from the team final competition due to a medical issue. She will be assessed daily to determine medical clearance for future competitions." It is likely that statement and the NBC report are saying the same thing.

It was a heartbreaking stream of news and the type of information it's hard to imagine a gymnast and her coaches revealing under USA Gymnastics' former regime. More than dancing between rotations or showing up to cheer on the men's team, the fact that Biles chose to place her mental and physical health above all -- during the Olympics -- and reveal her struggles to the world reminds gymnastics fans that if there is a cultural shift taking place within the sport, the athletes are leading it.

"It's been a long year, and I think we are too stressed out. We should be out here having fun," Biles said. "Sometimes that's not the case."

From a competitive standpoint, the news of Biles' withdrawal from the meet was anything but good news for a team already chasing the Russian Olympic Committee, behind by more than a point after the first rotation.

But from a human standpoint, the news hit harder. Biles has said throughout the past year that her return to the gym, especially after the COVID-19 pandemic delayed these Games, was made only more difficult by the fact that in order to chase her goals, she must represent an organization that failed her and her fellow survivors in the wake of the Larry Nassar abuse revelations. She has continued to call out the organization on its lack of transparency and has said that as long as she performs in an Olympic leotard bedazzled with "USA," she keeps a light shining brightly upon the survivors and their want for answers they have yet to receive.

Biles has said, though, that this time around, she wanted to compete for herself in a way she didn't in 2016, to push the limits of the sport simply to see what her body is capable of achieving. After Tuesday's meet, she broke down as she told reporters, "This Olympic Games, I wanted it to be for myself. But I was still doing it for other people. It hurts my heart that doing what I love has been kind of taken away from me to please other people."

Tuesday in Tokyo, that weight became too much to bear. And Biles responded by doing something gymnasts have been calling upon their sport to do for them for years: place athlete health and well-being ahead of gold medals. "I say put mental health first before your sport," Biles said of her decision. "I had to do what's right for me and not jeopardize my health and well-being. That's why I decided to take a step back and let [my teammates] do their work."

Biles said she will take Wednesday as "a mental rest day" and then make a decision on the rest of the Games. "We're going to see about Thursday," she said in reference to the individual all-around final. Biles qualified first into the all-around, and if she decides to defend her gold medal, she will be joined by Suni Lee. If she withdraws, individual athlete Jade Carey will take her place. "We're going to take it one day at a time," Biles said.

At the completion of the meet, as the teary-eyed members of the Russian Olympic Committee team celebrated their victory, Biles led her teammates toward them. "Good job, girls!" she said. She hugged each woman and congratulated her on her win. She lauded her teammates for winning a silver medal.

Instead of labeling this night a disappointment for the American team, perhaps it's a time to celebrate the ushering in of a new era: one in which gold medals take a backseat to mental health.

D'Arcy Maine contributed to this story.