UFC star Jorge Masvidal fired off a tweet Monday about his concerns when it came to biological women and transgender women competing in sports.

Masvidal’s tweet came on the heels of transgender University of Pennsylvania swimming star Lia Thomas winning a national championship in the 500 free. Masvidal suggested he was concerned for his daughter about the future of sports.

CLICK HERE FOR MORE SPORTS COVERAGE ON FOXNEWS.COM

Jorge Masvidal kicks Colby Covington in their welterweight fight during the UFC 272 event on March 5, 2022, in Las Vegas, Nevada.

Jorge Masvidal kicks Colby Covington in their welterweight fight during the UFC 272 event on March 5, 2022, in Las Vegas, Nevada. (Jeff Bottari/Zuffa LLC)

"What sport is left that is still biological girls vs biological girls? Want to put my daughter in a sport that is still fair to her," he tweeted.

Thomas’ prowess in the pool has been under the national spotlight for the last few months and sparked a debate over whether transgender women should be competing against biological women.

Through the debate, Thomas picked up a win in the 500-yard freestyle on Thursday. She set a program record with a 4:33.24 mark. Thomas was about three seconds off Georgia Tech’s pool record, which was set by Leah Smith of Virginia in 2016 with a mark of 4:30.81. Katie Ledecky holds the NCAA record with a 4:24.06 at the national championships.

In this race, Thomas beat out Virginia freshman Emma Weyant by more than one second and Texas freshman Erica Sullivan by at least two. Brooke Forde, who won a silver medal at the Olympics in Tokyo over the summer in the 4x200-meter freestyle, raced for Stanford and finished in fourth with a 4:36.18.

LIA THOMAS FINISHES LAST PLACE IN THE 100-YARD FREESTYLE FINAL AT NCAA CHAMPIONSHIPS

"I try to ignore it as much as I can," Thomas told ESPN after winning the race. "I try to focus on my swimming, what I need to do to get ready for my races. And just try to block out everything else."

Colby Covington (L) and Jorge Masvidal battle in their welterweight fight during UFC 272 at T-Mobile Arena on March 5, 2022, in Las Vegas, Nevada.

Colby Covington (L) and Jorge Masvidal battle in their welterweight fight during UFC 272 at T-Mobile Arena on March 5, 2022, in Las Vegas, Nevada. (David Becker/Getty Images)

Thomas has not done many interviews about her year. She told Sports Illustrated earlier this month she took issue with those who support her decision to live her life as a transgender woman but dismiss her from competing.

"The very simple answer is that I’m not a man. I’m a woman, so I belong on the women’s team. Trans people deserve that same respect every other athlete gets," she said.

Before that, her only public interview had been with "SwimSwam." She told the podcast she started to find "peace" after she felt like she was trapped inside a man’s body for years.

The NCAA updated its transgender participation policy back in January to defer to the guidance of each sport’s governing body. The NCAA announced that its policy would become effective in March, starting with the Division I Women’s Swimming and Diving Championships.

Lia Thomas looks on after winning the Women's 500 Yard Freestyle during the 2022 NCAA Division I Women's Swimming & Diving Championship at the McAuley Aquatic Center on the campus of the Georgia Institute of Technology on March 17, 2022, in Atlanta, Georgia.

Lia Thomas looks on after winning the Women's 500 Yard Freestyle during the 2022 NCAA Division I Women's Swimming & Diving Championship at the McAuley Aquatic Center on the campus of the Georgia Institute of Technology on March 17, 2022, in Atlanta, Georgia. (Mike Comer/NCAA Photos via Getty Images)

CLICK HERE TO GET THE FOX NEWS APP

USA Swimming updated its policy shortly after requiring transgender athletes who are competing at an elite level to have small levels of testosterone — half of what Thomas was allowed to compete with — for at least 36 months before being eligible, but the NCAA said weeks later that the Administrative Subcommittee of the Committee on Competitive Safeguards and Medical Aspects of Sports (CMAS) decided that it wouldn’t alter its testosterone guidance, stating that "implementing additional changes at this time could have unfair and potentially detrimental impacts on schools and student-athletes intending to compete in 2022 NCAA women's swimming championships."

Fox News’ Paulina Dedaj and the Associated Press contributed to this report.