While appearing on the "TODAY" show on Tuesday, the 27-year-old former Team USA gymnast and three-time Olympic gold medalist revealed her reaction to Biles being pulled out of the team competition, saying she's "completely devastated" and "sick to [her] stomach" over the news.
"It's horrible," Raisman said. “I know that all of these athletes dream of this moment for their whole entire lives, and so I'm just completely devastated. I am obviously so worried and just hoping that Simone is OK."
"I also am just thinking about the mental impact that this has to have on Simone," she added. "It's just so much pressure and I've been watching how much pressure has been on her in the months leading up to the Games and it's just devastating. I feel horrible."
On Tuesday, Biles, 24, withdrew from the women's team finals following a low-scoring attempt on vault and was pulled out "due to a medical issue."
"Simone Biles has withdrawn from the team final competition due to a medical issue," USA Gymnastics said in a statement. "She will be assessed daily to determine medical clearance for future competitions."
However, after the team finals -- in which Team USA went on to win a silver medal despite Biles' exit -- Biles announced that she dropped out due to mental health issues, not because of a physical injury.
"Just my pride is hurt a little bit," Biles told reporters, per TMZ Sports. "After the performance that I did, I didn’t want to go into the other events so I thought I would take a step back."
"I have to focus on my mental health and not jeopardize my health and well-being," she added.
According to the outlet, Biles will be using Wednesday as a "mental health day" and hasn't ruled out competing in the individual all-around final on Thursday. Biles -- who is the most decorated gymnast of all time -- told "TODAY's" Hoda Kotb that she's "going to be taking it day by day."
Speaking to "TODAY" before more details about Biles' exit were revealed, Raisman shared that she's "praying" her former teammate will "be able to compete" on Thursday.
Raisman -- who was teammates with Biles during the 2016 Rio Olympics -- also pointed out the amount of "pressure" that has been put on Biles.
"I think that Simone is the biggest story going into the Olympics, so this is just -- it's really, really devastating," she said. "I think it's also just really important to think about how much pressure has been on her and there's only so much that someone can take."
"She's human and I think sometimes people forget that," she continued. "And Simone, just like everyone else, is doing the best that she can."
Raisman added that Biles "has more pressure than any other gymnast I've ever seen in my lifetime."
Former U.S. Olympic gymnast Laurie Hernandez -- who competed on Team USA with Raisman and Biles during the Rio Olympics -- also reacted to the news while speaking to "TODAY," saying that Biles is under "immense pressure."
MyKayla Skinner -- who was an alternate in the 2016 U.S. Olympic gymnastic team and competed at the Tokyo Games as an individual -- told "TODAY" that her "heart broke" for Biles.
"I can't even imagine what she's going through right now. I wish I could run down there and give her a big hug," explained Skinner, whose time at Tokyo came to an end earlier this week after she failed to qualify for any event final.
Meanwhile, celebrities, including former Olympians, have been sending Biles messages of support on social media.
"Someone said it best. @Simone_Biles already won," Hoda Kotb tweeted. "She is a class act. Withdrew from team competion [sic] after vault... stayed and cheered on her teammates... got them chalk for their hands.. encouraged.. hugged them. She already won. Congrats on the silver medal! @TeamUSA @USAGym."
British-American freeskier Gus Kenworthy shared a photo of himself with Biles and the U.S. women's gymnastics team -- and said he's "proud" of Biles over her decision to withdraw from the competition.
"I can only imagine the immense pressure that Simone Biles felt going into tonight's team event with the weight of a country on her shoulders, the whole world watching and all eyes on her," he captioned the photo. '"The greatest of all time' would be a merciless title to have to live up to over and over again. She ended up withdrawing from the competition and I just want to say that I’m sincerely proud of her for doing so."
"It took tremendous courage for her to listen to her instincts and choose preservation (both mental and physical) instead of being caught up in all of the noise," he added. "I'm also truly proud of the rest of the young women on Team USA for adapting and persevering to earn Olympic silver! Congratulations ladies, I feel honored to have witnessed it!!! #Tokyo2020"
See more reactions in the posts, below.
Someone said it best. @Simone_Biles already won. She is a class act. Withdrew from team competion after vault... stayed and cheered on her teammates... got them chalk for their hands.. encouraged.. hugged them. She already won. Congrats on the silver medal! @TeamUSA@USAGym