On Thursday, Lee, 18, and fellow Team USA gymnast Jade Carey finished the women's gymnastics individual all-around in first and eighth place, respectively, at the Ariake Gymnastics Center.
Lee ended the competition with 57.433, just ahead of silver medalist Rebeca Andrade of Brazil's 57.298, and the Russian Olympic Committee's Angelina Melnikova, who finished with 57.199.
Speaking with reporters after the event, Lee said that she could not believe her gold-winning feat. "Coming into this competition, I didn't even think that I could be competing for a gold medal," she said. "I was coming to compete for a silver medal. To be here, it's crazy."
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Teammate Simone Biles — who had been a favorite to win the individual all-around — pulled out of the event earlier this week.
"I feel like this whole season I've been second to her," she added, noting that she tried not to "focus on it though" or else she "knew I would get too nervous."
Photo by Jamie Squire/Getty Images
Lee, a teen from Minnesota, earned her spot in the individual all-around competition after her standout performance during the qualifiers, which she followed up in the team final with a score of 15.400 on the uneven bars, performing a routine with the highest difficulty score in the world.
After her win, Lee — who finished on floor — beamed and wiped away tears of joy as she hugged Carey, 21, and her coaches.
Heading into the Games, she was the first Hmong American Olympic gymnast and is now the first Hmong American Olympic gold medalist. With Lee's win, the U.S. has now also won five straight women's all-around golds, starting with Carly Patterson in 2004.
Earlier this year, Lee told PEOPLE that being an Olympian means "the world for me," adding "I want to do it for my family and coaches obviously, but I also want to do it for myself. I've just been through so much."
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While chatting with reporters on Thursday, Lee also touched more upon how much her gold medal means to her, noting that there were previous times in her life when she considered quitting gymnastics altogether.
"The waiting game was something that I hated so much ... but when I saw that my score went on top, it was so emotional. I didn't think I'd ever be here," she said. "There was a point where I wanted to quit, so to even say that I'm an Olympic gold medalist and be here is just so crazy."
When asked at what points during her life made her consider quitting her beloved sport, Lee expressed that the COVID-19 pandemic played a large role.
"Quarantine, for sure, and then when I broke my foot [were times I thought of quitting], because it wasn't getting any better and it just felt like I wasn't ever going to be able to make it to the Olympics," she explained.
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Due to international spectators being barred from attending Olympic events in Tokyo, Lee's friends and family have been cheering her on from home. However, it was bittersweet not being able to share the moment with them in person.
"This is our dream," she said of her father, who has been one of her biggest supporters. "It sucks that he couldn't be here."
However, Lee was able to celebrate the good news with her family virtually. "Before the medal ceremony I FaceTimed them and I talked to them. We were all just crying on the phone," she said. "It was a very surreal moment."
"My parents are just the most amazing people in my life, I love them so much," she added.
Jamie Squire/Getty Images From left to right: Bronze medalist Angelina Melnikova of Team ROC, gold medalist Sunisa Lee of Team United States and silver medalist Rebeca Andrade of Team Brazil
Speaking with Today after his daughter's big win, her father said, "we're so proud of her."
"I'm going to tell her I'm so proud of her," he added. "I want to tell her team that no matter what, you all support her and I want to tell Simone [Biles] that she truly is the GOAT because she let my baby girl bring the gold medal."
To learn more about Team USA, visit TeamUSA.org. Watch the Tokyo Olympics now on NBC.