On Saturday, Simone Biles will compete in the women's vault final at the Paris Olympics, a competition she pulled out of three years ago.
Vault is one of Biles' best events. She has two skills named after her on the apparatus and has put up some of the highest scores at international competitions.
But at the Tokyo 2020 Games, the vault was an opponent of its own.
Biles faced a mental block common for gymnasts, called the twisties.
The twisties are a type of gymnastics block where the athlete loses sense of where their body is in the air and how they're twisting. Since the ability to have spatial and air awareness is crucial for success and safety in the sport, having a case of the twisties can be extremely dangerous for the gymnast.
One of Biles' teammates from the 2016 Olympics, current NBC Olympics gymnastics analyst Laurie Hernandez, described the feeling to Olympics.com.
"The rhythm is off, and your brain will, like, stutter step for half a second, and that's enough to throw off the whole skill," Hernandez said.
At the team final event in Tokyo, Biles went up to perform her vault, called an amanar. Instead of the usual two and a half twists, she only competed one and a half twists due to the mental block she was facing.
Biles had to withdraw from the remainder of the team final, as well as from the all-around final, floor exercise final and vault final.
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This year, she already got her redemption. She won both a team gold medal and the coveted all-around gold medal so far, and isn't done competing yet.
On Saturday, she will compete in the vault final, this time with upgraded vaults, including one named after her. She is expected to perform her signature Yurchenko double pike as one of her two routines.
Biles is heavily favored to win the vault final but will be face one of her biggest competitors: Rebeca Andrade of Brazil.
Andrade won the silver medal in the all-around on Thursday, coming close to Biles' winning score. She also chose not to perform a triple twisting Yurchenko vault, which she submitted to be named after her if she does use it.
Biles has looked solid throughout her time in Paris so far, and her three remaining competitions of balance beam, vault and floor exercise give her even more chances to medal.
The women's vault final will stream at 9:20 a.m. CT on Saturday on NBC and Peacock.
