Ryan Murphy is going back to the Olympics to defend America’s dominance in the backstroke.

At age 36, Matt Grevers won’t get another shot.

Murphy held on to win the 100-meter backstroke at the U.S. Olympic trials on Tuesday night, the first of two spots he hopes to claim in his bid to pull off another backstroke double at the Tokyo Games.

He won both the 100 and 200 back in Rio, extending a U.S. winning streak in the men's events that began after the 1992 Barcelona Games — three years before the 25-year-old Murphy was born.

His winning time was 52.33 seconds.

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Grevers, who won the 100 back at the 2012 London Games and just missed making the U.S. team five years ago, failed again in what was surely his final bid to make his third Olympics. He finished sixth in 53.27.

The expected second spot on the Olympic team went to Hunter Armstrong (52.48).

On the women's side, former world record holder Regan Smith claimed her first Olympic berth in the 100 back.

The 19-year-old from Lakeville, Minnesota, touched first in 58.35, not as fast as her then-record time at the 2019 world championships (57.57), but surely good enough to set her up as one of the gold medal contenders in Tokyo.

"The American backstroke is a powerhouse," Smith said. "We have so much depth. I knew it was going to be extremely tough to come out on top."

Rhyan White is also likely to be Tokyo-bound after finishing second in 58.60.

Kieran Smith, who has never even been on the national team (and is no relation to Regan Smith), secured his second race at the Tokyo Games with a victory in the 200 freestyle.

The 21-year-old native of Ridgefield, Connecticut, who attends the University of Florida, added to his victory in the 400 free with a winning time of 1 minute, 45.29 seconds.

Townley Haas, who finished fifth in the 200 free at the Rio Games, earned a sure spot in the 4x200 free relay and a likely individual race as the second American by taking the runner-up spot in 1:45.66.

Drew Kibler and Andrew Seliskar finished third and fourth, respectively, to also earn Olympic berths as relay swimmers.

Coming off a relatively slow winning time in the 400 freestyle, Katie Ledecky took on her busiest day of the meet with the preliminaries of the 1,500 free and the prelims and semifinals of the 200 free.

Ledecky was top qualifier in the metric mile in the morning, and came back to post the fastest time in the 200 semis in the evening (1:55.83). She will try to lock up two more races for Tokyo in the finals Wednesday, which are about an hour apart.

"It was a good day," she said. "Of course, my biggest day of racing from top to bottom. A long day at the office. It was good to get some rest in between."

Ledecky said she's still adjusting to racing before fans after the coronavirus pandemic shut down the sport and forced the trials and the Olympics to be delayed a year.

"I was a lot more nervous than I expected to be," she said. "I felt like we went from zero to 100 when it comes to fans. Being in that environment, it just takes some time for me to get used to."