She was just 15 years old, a reserved high schooler who had surprisingly made the U.S. swim team for the London Games. Then she went out and shocked the world, beating everyone in the 800-meter freestyle.

Twelve years to the day, Ledecky did it again.

Not a stunner, but one for the ages.

Gold medal No. 9.

Ledecky capped another stellar Olympics by becoming only the second swimmer to win an event at four straight Summer Games, holding off Ariarne Titmus, the "Terminator," to win the 800 free Saturday night.

It was Ledecky's second gold medal in Paris and the ninth of her remarkable career, which marked another milestone.

She became only the sixth Olympian to reach that figure, joining swimmer Mark Spitz, track star Carl Lewis, Soviet gymnast Larisa Latynina and Finnish runner Paavo Nurmi in a tie for second place.

The only athlete to win more golds: swimmer Michael Phelps with 23.

Ledecky was very aware of the significance of the date.

“Every Aug. 3, the video (of her first Olympic gold) gets posted somewhere and you kind of reminisce,” she said. “So, when I saw it was Aug. 3, I was like, Oh boy, I've got to get the job done.'”

That she did, going faster than her winning time in Tokyo to finish in 8 minutes, 11.04 seconds. Titmus was right on her shoulder nearly the entire race, but Ledecky pulled away in the final 100.

Titmus, who beat Ledecky in the 400 freestyle, settled for silver at 8:12.29. The bronze went to another American, Paige Madden at 8:13.00.

Phelps had been the only swimmer to win the same event at four straight Olympics, taking gold in the 200 individual medley at Athens, Beijing, London and Rio de Janeiro.

Now he's got company.

Titmus added some perspective to Ledecky's consistency over the last dozen years, noting where she was when the American won that first gold in London.

“I was in grade six in primary school,” Titmus said. “That's how remarkable she is.”

Their friendly rivalry has driven both to greater heights. They each won two golds and four medals at these games, which pushed Ledecky to 14 overall and left the 23-year-old Aussie with four golds and eight medals in her career.

"To think that ... I challenged her into her fourth consecutive in the 800 is pretty cool,” Titmus said. “I feel very honored and privileged to be her rival, and I hope I've made her a better athlete. She has certainly made me become the athlete I am. I felt so privileged to race alongside her.”

Ledecky has dominated the distance freestyle events over the last dozen years — and isn't done yet. She's made it clear she plans to keep swimming at least through the 2028 Los Angeles Games.

“It's not easy,” Ledecky said. “I'll take it year by year, and we'll see if I can keep giving everything I've got for as long as I have left in me.”

Another gold for Canadian teenager Summer McIntoshSummer McIntosh stamped herself as one of the swimming stars of the Paris Olympics with her third individual gold medal, winning the 200 individual medley.

The 17-year-old Canadian chased down American Alex Walsh and held off another U.S. swimmer, Kate Douglass, to finish in an Olympic record of 2:06.56.

Douglass grabbed the silver in the star-studded final at 2:06.92, but the Americans lost the bronze when Walsh, the silver medalist in this event at Tokyo who recorded a time of 2:07.06, was disqualified because she did not finish the backstroke segment on her back.

Kaylee McKeown, who touched fourth, was bumped up to the bronze at 2:08.08.

It was a bitter blow for Walsh, whose younger sister, Gretchen, has won a gold medal and two silvers in Paris.

McIntosh set several world records ahead of the Paris Olympics, and she backed up the enormous expectations by claiming a starring role at La Defense Arena along with Léon Marchand and Ledecky.

McIntosh also won gold medals in the 200 butterfly and 400 IM, plus a silver in the 400 freestyle. She fell just 0.88 seconds — the margin of her loss to Titmus — shy of matching Marchand's four individual golds.

“It's pretty surreal,” said McIntosh, who became the first Canadian athlete to win three golds in a single Olympics. “I'm just so proud of myself and how I've been able to recover and manage events."

U.S. sets world record in mixed relayThe United States made up for a disappointing showing in Tokyo by setting a world record in the 4x100 mixed medley relay.

Ryan Murphy, Nic Fink, Gretchen Walsh and Torri Huske held off China for a winning time of 3:37.43, breaking the mark of 3:37.58 set by Britain when it won gold in the wild and woolly event's Olympic debut three years ago.

With each team picking two men and two women, the U.S. and China both went with their male swimmers in the first two legs.

Murphy put the U.S. in front on the backstroke, China's Qin Haiyang slipped past Nic Fink on the breaststroke, but Walsh stormed back in front for the Americans on the butterfly before Huske held off Yang Junxuan to secure the gold.

For Huske, it was her second gold to go with two silvers in Paris.

The Chinese team, which also included Xu Jiayu and Zhang Yufei, took silver in 3:37.55. The bronze went to Australia in 3:38.76.

Marchand swam the breaststroke leg for France but couldn't add to his already impressive haul. The French finished fourth, more than two seconds behind the Aussies.