The Houston Texans safety, 26, shared several photos of Biles on Instagram on Thursday, penning a heartfelt note to his gold medalist girlfriend.
"Imma ride with you through whatever baby ❤️" he wrote. "Your strength and courage is unmatched and you inspire me more and more everyday SB 🤞🏽"
He continued, "You always gone be my champ baby and don't you ever forget that, i love you so much and i can't wait till you come home and i get to see that beautiful smile again. You know I'm always here for you baby ❤️❤️"
Earlier this week, Biles opted out of both the women's gymnastics individual all-around and the women's gymnastics team final in Tokyo.
"After further medical evaluation, Simone Biles has withdrawn from the final individual all-around competition at the Tokyo Olympic Games, in order to focus on her mental health," U.S.A. Gymnastics wrote in a statement Wednesday. "Simone will continue to be evaluated daily to determine whether or not to participate in next week's individual event finals."
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Biles addressed her decision with reporters, citing her mental health and noted that she was "dealing with some things internally."
RELATED VIDEO: Nastia Liukin Writes Powerful Note in Support of Simone Biles: 'You're Leaving as a Hero'
The 24-year-old's final four events — the individual finals vault, beam, uneven bars and floor — begin this coming Monday. It remains unclear if she'll participate in those, or will opt out as well.
Biles spoke out again a tweet Wednesday, writing: "The outpouring love & support I've received has made me realize I'm more than my accomplishments and gymnastics which I never truly believed before."
To learn more about Team USA, visit TeamUSA.org. Watch the Tokyo Olympics now on NBC.