ATLANTA -- With a small group of protesters outside, Lia Thomas qualified for the 500-yard freestyle final at the NCAA women's swimming and diving championships Thursday morning.

Thomas finished in 4 minutes, 33.82 seconds in her debut at the championships to qualify first for Thursday night's final. It was the first time she has improved on her time in the event since the December meet where she swam a 4:34.06, which was the top NCAA time of the season entering the championships.

Nine protesters from the organization Save Women's Sports gathered outside the McAuley Aquatic Center at Georgia Tech to protest Thomas' participation. The protesters waved signs that read, "Support fair sports for women and girls," while one protester wore a shirt that read, "That man is a cheat," in bold, white letters. Thomas is a transgender woman who previously competed three seasons on the Quakers men's team.

"I came to support women and girls," Jeanna Hoch, who traveled from Denver and has two daughters, told ESPN. "They do not have the same opportunities that I had. There is no single-sex competition anymore."

Spectators stopped to take photos with the group, and some accepted pamphlets and stickers to show support.

Thomas made national headlines after she posted the nation's top times in the 200 and 500 freestyle in December at the Zippy Invitational in Akron, Ohio. In February, she won Ivy League titles in the 100, 200 and 500 freestyle and was the top points scorer of the meet. She is slated to compete in all three events at the NCAA championships.

If she wins a championship in Atlanta this week, Thomas will be the first known transgender person to claim a Division I national title.

Also in Thursday night's final will be Stanford swimmer and Tokyo Olympian Brooke Forde, who qualified sixth with a time of 4:38.19 and finished second behind Thomas in their heat. Forde already has a national title at this meet as part of Stanford's dominant win in the 800 freestyle relay Wednesday night.

Forde is one of just a few of Thomas' competitors who have shared their perspective on swimming against her. Forde released a statement in January in which she said she had no problem swimming against Thomas, and she said Wednesday night that she still feels that way.

"I'm going to swim my race the way I want to no matter who I'm next to and who else is here," Forde said.