The U.S. Olympic Gymnastics Trials begin Thursday in St. Louis. At the end of the day on Saturday for the men and Sunday for the women, the four-person squads for the Tokyo team event will be named, as well as an additional specialist on each side. The top two finishers in the all-around competition automatically qualify for Tokyo for the women -- and for the men, too, provided the runner-up finishes in the top three on three of the six apparatuses. The third and fourth team members will be selected by committee.

The women have two additional individual spots, but Jade Carey has already secured one for herself, and one will be selected by committee. The men have one additional individual spot to fill. 

Here's a look at the three biggest storylines to follow:

Barring disaster, there’s no question as to who will win the women’s meet. Simone Biles has competed twice in the last month -- her first two contests since the 2019 World Championships -- and blew away the field in both. Her degree of difficulty, coupled with her relentless ability to execute under pressure, is simply untouchable in most cases. At the U.S. Classic, Biles debuted a Yurchenko double pike vault, never before attempted by a woman in competition. She didn’t perform that vault at the U.S. Championships two weeks ago, but it could return in St. Louis as Biles aims to perfect it ahead of Tokyo. Even without all of her hardest skills, Biles won a historic seventh all-around national title by nearly five points.

Asked about her motivation in April, Biles said: "It's more stressful whenever I go out and compete because I’m trying to be better than I was at the last meet. ... I’m trying to beat myself."

Biles added that she sometimes wonders if she can still outdo herself. "Sometimes you get caught up in the moment and it's just scary because I go out and I'm like, 'Can I do it again? Can I be this good?'" she said.

Four women will end up on the Tokyo all-around team, but the race for the fourth team spot is very much up in the air. Jordan Chiles, Biles’ teammate at the World Champions Centre, has had a breakout 2021. She won the Winter Cup in February, then took second at the U.S. Classic and third at Nationals and is now expected to end up on the Tokyo team. Three-time 2019 World Championships medalist Sunisa Lee, the only gymnast other than Biles to win an individual title at Nationals, is also a strong candidate to be picked or automatically qualify. Outside of those three, it’s anyone's game: at the U.S. Championships, the fourth- through ninth-place finishers were separated by less than a point.

One woman, however, is likely out of the running for a team berth: Jade Carey. Carey qualified for the Games as an individual before emerging as a potential team contender. After she finished sixth at Nationals, debate arose as to what would happen if she put up a stronger finish at Trials (chaos, potentially, if she were to be in the top two), but Carey somewhat quashed the speculation last week by saying she has "every intention" of accepting the individual spot.

Two-time Olympian Sam Mikulak, 28, is retiring after Tokyo -- a decision he made during the COVID-19 pandemic because of his mental and physical health -- so Trials will be his last domestic meet. The six-time all-around national champion struggled on the opening day of the U.S. Championships, but ended up third overall after a stellar second day. It was only the second time since 2013 that he didn’t win the all-around title, however, and the first when he competed on every apparatus. In his stead, Stanford standout Brody Malone took the crown and is expected to be the frontrunner to make the Olympic Team. Malone is a two-time NCAA all-around champion but has yet to compete on a senior-level international team.

“I’m just glad that there’s someone to fill my shoes when I’m gone — and overstep me right now,” Mikulak said after Nationals. “My goal is just to make the [Olympic] team. I know I’m not at my best, and I’m just trying to keep up with him.”

While Mikulak should still make the team, he would be joined by a number of Olympic newcomers that might include 2017 U.S. all-around champion Yul Moldauer, 2019 World Championships team member Shane Wiskus, or Akash Modi, the 2016 Olympic alternate trying to make his first team outright at age 26.