OMAHA, Neb. — One by one, some of America’s biggest swimming stars are going down at the Olympic trials.

First, Ryan Lochte. Then, Missy Franklin.

Lochte, an 11-time Olympic medalist but slowed by a groin injury, missed out on his second chance to make the team in an individual event with a fourth-place finish in the 200-meter freestyle. There was some consolation: Lochte at least clinched a spot in the 4x200 relay, so he’ll be in Rio.

Franklin can’t say that yet. The bubbly star of the 2012 London Games struggled to a seventh-place finish in the 100 backstroke, denying her a chance to defend the gold medal she won four years ago.

“I think I am feeling more pressure than I ever have before,” said Franklin, who still has more chances to make the team. “But part of the process is learning how to move forward, and all I cann do is the best I can do.”

Racing just 23 minutes after qualifying for the final of the 200 free, the 21-year-old Franklin couldn’t pull off the grueling double. She finished nearly a body length behind winner Olivia Smoliga and runner-up Kathleen Baker, who will represent the U.S. in what was once Franklin’s signature event.

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The only swimmer to finish behind Franklin was 12-time gold medalist Natalie Coughlin. The 33-year-old likely missed out on her best chance to make the team in an individual event, though there’s a chance she could still qualify in a relay.

In the men’s 200 free, Lochte was second at the final turn but couldn’t hold on, either. Townley Haas surged to the victory, followed by Conor Dwyer.

“I’m just happy that I’m going to Rio,” Lochte said. “You can never go in knowing that you’re going to make the team, just because the U.S. is one of the hardest countries to make the Olympic team.”

For good measure, another stalwart of the 2012 U.S. team failed to qualify for Rio. Matt Grevers, the defending Olympic gold medalist in the men’s 100 backstroke, finished third behind Ryan Murphy and David Plummer.

Another Olympic gold medalist, Jessica Hardy, finished sixth in the 100 breaststroke to also miss out on the U.S. team. Lilly King and Katie Meili were 1-2 in the final, extending what has become a definite changing of the guard for the American team in Omaha.