Caeleb Dressel and Emma McKeon earned milestone medals at the Olympic pool before the race to determine the fastest man in the world took center stage.

Dressel won two more gold medals on Sunday to give him five in the Tokyo Olympics, winning the 50-meter freestyle and putting the Americans ahead to stay in the 4x100 medley relay on their way to a world record.

CLICK HERE FOR MORE SPORTS COVERAGE ON FOXNEWS.COM

"I’m proud of myself. I feel like I reached what my potential was here at these Games," Dressel said. "It was just really fun racing."

Dressel join Americans Michael Phelps, Mark Spitz and Matt Biondi, as well as East Germany’s Kristin Otto, as the only swimmers to win as many as five golds at a single Olympics. Phelps did it three times.

McKeon became the first female swimmer and second woman in any sport to claim seven medals at one Olympics. Four of them were gold, the other three bronze.

McKeon won the 50 free and took the butterfly leg on Australia's winning effort in the women’s 4x100 medley relay.

The only other woman to win seven — in any sport — was Soviet gymnast Maria Gorokhovskaya, who claimed two golds and five silvers at the 1952 Helsinki Games.

"It still feels very surreal," said McKeon, a 27-year-old from Brisbane. "It’s going to take a little bit to sink in. I’m very proud of myself."

One of the marquee events of the Games was held later Sunday in the first Olympics without Usain Bolt in the finals of the 100-meter dash since 2004. Bolt won the 100 at the past three Olympics.

American sprinter Trayvon Bromell came into the Games as the favorite but nearly didn't make the semifinals. He’ll be challenged by teammate Ronnie Baker, Andre De Grasse of Canada and Akani Simbine of South Africa.

TEE IT UP

Xander Schauffele won the Olympic gold medal in golf in a tense finish.

Schauffele was tied for the lead with Rory Sabbatini of Slovakia with two holes to play. The American made birdie from 6 feet on the 17th hole to regain the lead. Then after a bad tee shot that forced him to play short of the water, he hit wedge to 4 feet and made the par to win.

Sabbatini set an Olympic record with a 61 and won the silver.

SIDELINED

Simone Biles will not defend her Olympic gold medal on floor exercise.

USA Gymnastics said the six-time Olympic medalist has opted not to compete on floor. She won gold in the event in Rio de Janeiro and placed second in qualifying last week. Jennifer Gadirova of Britain will replace Biles in Monday’s finals.

Biles has not decided whether to participate in Tuesday’s balance beam final, USA Gymnastics said.

Biles is dealing with a mental block that in gymnastics is referred to as "the twisties." She is having trouble figuring out where her body is in relation to the ground when in the air.

BEACHED AMERICANS

Two American teams are out at the Olympic beach volleyball venue.

A Qatari pair that is ranked No. 1 in the world beat Nick Lucena and 2008 gold medalist Phil Dalhausser 14-21, 21-19, 15-11 in the first round of knockout play.

The U.S. women’s team of Sarah Sponcil and Kelly Claes also lost in three sets to Heather Bansley and Brandie Wilkerson of Canada after winning the first set.

Claes and Sponcil entered the Games as the hottest team in the world, winning the last two events of the pandemic-extended qualifying period to grab the second U.S. spot in Tokyo. In the process, they knocked out five-time Olympian Kerri Walsh Jennings.

"Huge learning moment for us," Claes said. "It sucks right now. It’s probably going to suck for a few weeks. But probably looking back I’ll for sure look at that and take that into account. But right now, like, it stinks."

MIX IT UP

The top-seeded Czech team of Barbora Krejcikova and Katerina Siniakova won gold in women’s doubles. The Czechs beat the Swiss team of Belinda Bencic and Viktorija Golubic 7-5, 6-1.

Bencic won gold in singles a day earlier by beating Czech player Marketa Vondrouova.

Laura Pigossi and Luisa Stefani of Brazil took the bronze.

CLICK HERE TO GET THE FOX NEWS APP

DEBUT MEDAL

Charlotte Worthington of Britain put on a show in BMX freestyle’s Olympic debut, landing the first 360 backflip in women’s competition to knock off American rival Hannah Roberts.

Roberts, a three-time world champion at 19, set the bar in her opening run, landing a backflip with a tailspin for a 96.1.

Worthington crashed on her first run, but pulled out all the stops in her second. The 25-year-old added a front flip to her 360 backflip and closed with another backflip for a 97.5.

Logan Martin of Australia won gold in the men’s event.