Kentucky swimmer Riley Gaines slammed the University of Pennsylvania’s decision to nominate Lia Thomas for the NCAA’s Woman of the Year award Friday.

Thomas, who is transgender, became the first trans woman to win titles at the Ivy League and NCAA championships

But her prowess in the pool ignited a hotly contested debate over whether transgender woman should be permitted to compete in sports against biological women.

Gaines tweeted her opinion, saying the NCAA is making the highest award in collegiate athletics "worthless."

CLICK HERE FOR MORE SPORTS COVERAGE ON foxnews.1eye.us

Lia Thomas at the NCAA Championships

Lia Thomas after winning the 500-yard freestyle during the 2022 NCAA Division I women's swimming and diving championships at the McAuley Aquatic Center on the campus of the Georgia Institute of Technology March 17, 2022, in Atlanta. (Mike Comer/NCAA Photos via Getty Images)

"Being the real girl in that photo and also University of Kentucky's nominee for NCAA WOTY, this is yet another slap in the face to women. First a female national title and now nominated for the pinnacle award in collegiate athletics," she wrote in a tweet response to Outkick founder Clay Travis. "The @NCAA has made this award worthless.

"This award combines athletic performance with academics, service, and character. What character has Thomas shown other than sheer selfishness and entitlement? The disrespect and disregard for the other female athletes in Thomas' interviews is eye opening."

Gaines was also nominated for NCAA Woman of the Year by the University of Kentucky after she finished her career in the pool. She won three individual conference titles in the SEC, broke two SEC records, had 12 All-America awards and graduated with summa cum laude honors. She finished behind Thomas in the 200-yard freestyle at the NCAA championships earlier this year.

LIA THOMAS NOMINATED BY UNIVERSITY OF PENNSYLVANIA FOR NCAA 'WOMAN OF THE YEAR' AWARD

"This award recognizes not only athletic performance but also academics, service and character, so to be thought of as someone who embodies all of those things is extremely humbling," Gaines said in a news release on the school’s athletics website. "I’m aware I was up against a department full of amazing female student-athletes, so I’m very grateful and always proud to be a Wildcat. I have so much love for UK and Big Blue Nation."

Riley Gaines waves to the crowd

Kentucky swimmer Riley Gaines reacts after finishing tied for fifth in the 200 freestyle finals at the NCAA swimming and diving championships March 18, 2022, at the McAuley Aquatic Center in Atlanta. (Rich von Biberstein/Icon Sportswire via Getty Images)

Each NCAA member school nominates a Woman of the Year. Each conference then reviews the nominations from its member schools and submits its conference nominee to the NCAA. Nominees who compete in sports not sponsored by their school’s main conference and independent nominees will be sent to a separate pool of nominations and considered by a committee.

The organization then identifies the top 30 and, from there, selects three finalists from each pool. From the nine finalists, the NCAA will choose a winner.

UPenn athlete Lia Thomas at nationals

University of Pennsylvania swimmer Lia Thomas and Kentucky swimmer Riley Gaines react after finishing tied for 5th in the 200 freestyle finals at the NCAA swimming and diving championships March 18, 2022, at the McAuley Aquatic Center in Atlanta. (Rich von Biberstein/Icon Sportswire via Getty Images)

The nomination of Thomas comes after FINA, the governing body for international swimming, voted to approve new polices for transgender swimmers.

Riley Gaines at the Swimming and Diving Championships

Kentucky swimmer Riley Gaines swims the 200 butterfly prelims at the NCAA swimming and diving championships March 19, 2022, at the McAuley Aquatic Center in Atlanta. (Rich von Biberstein/Icon Sportswire via Getty Images)

CLICK HERE TO GET THE FOX NEWS APP

The newly approved "gender inclusion policy" only permits swimmers who transitioned prior to the age of 12 to participate in women's events.