BUDAPEST, Hungary -- Katie Ledecky extended her record haul of medals from the world swimming championships to 22 with her latest 800-meter freestyle win Friday.
Ledecky clocked 8:08.04 to win the event for the eighth consecutive time at a worlds or Olympic Games. She is the first swimmer to win a specific individual event at five successive worlds.
The American finished more than 10 seconds ahead of her rivals. Australia's Kiah Melverton was 10.73 behind in second, and Italy's Simona Quadarella was 10.96 behind for third.
Ledecky was under four seconds off the world record she set at the 2016 Olympics.
"I think back to London," Ledecky said of her first win at the 2012 Olympics. "I made it a goal to not be a one-hit wonder and here we are 10 years later, so I'm really proud of that and still excited for the future as well."
It's her 19th gold at a worlds and her fourth this week. She helped the United States win the 4x200 freestyle relay final Wednesday, two days after she won the 1,500 freestyle, which came two days after she won the 400 freestyle on the first day of racing in Budapest.
She completed the 400/800/1,500 triple for the fourth time at a single worlds, more than all the other swimmers who managed the feat combined. Germany's Hannah Stockbauer, Australia's Grant Hackett and China's Sun Yang each managed it once.
Ledecky has the most medals for a female swimmer in world championships history. Only Michael Phelps, who won 26, has more.
"This is just the start, which is tremendously exciting for me," said Ledecky, who added that changes to her approach are paying off. "There have been a couple of things that are a little different -- training with the men, Bobby [Finke] and Kieran [Smith] and Trey [Freeman], who are all here, to try to keep up as much as I can and they push me. I hope that they feel that they've benefited from me being there, and just a lot of work on my stroke and my rhythm."
In other events, Australia set a world record in the mixed 4x100 freestyle final.
Jack Cartwright, Kyle Chalmers, Madison Wilson and Mollie O'Callaghan finished in 3:19.38 to shave two-hundredths of a second off the record set by the United States at the last worlds in Gwangju, South Korea, in July 2019.
The Australians also ended the Americans' three-title winning run from 2015 to 2019 in this event. All four were won with a world record.
"I don't think there was any mention or any expectation or even a thought about being able to break that," Wilson said. "So to do that and see that at the end was just unbelievable and a real surprise for us."
Canada's team of Joshua Liendo, Javier Acevedo, Kayla Sanchez and Penny Oleksiak was 1.23 behind the Australians for silver, and the United States team of Ryan Held, Brooks Curry, Torri Huske and Claire Curzan was third, 1.71 behind.
Canada's silver was the country's ninth medal this week, eclipsing the eight it won in Gwangju.
Ben Proud won Britain's first gold of the championships, clinching the men's 50 freestyle in 21.32 -- 0.09 ahead of American Michael Andrew and 0.25 ahead of France's Maxime Grousset.
"We're missing quite a few key players in the pool today," Proud said, referring to the absences of Caeleb Dressel, Florent Manaudou and Bruno Fratus. "The whole podium from the Olympics last year wasn't in the final."
Dressel was due to race but withdrew from the worlds for unspecified reasons Wednesday.
"It's not the same without him," Proud said. "As soon as he was out, that quite changed the dynamics of the competition. A lot of people had a different type of pressure leading in."
Sarah Sjostrom won her fourth consecutive 50 butterfly title, clocking 24.95 to head off Melanie Henique of France and Yufei Zhang of China for a record-equaling eighth gold medal in butterfly events at a worlds.
American Torri Huske was sixth, 0.50 behind Sjostrom, who claimed her 18th individual medal at the worlds. Only Phelps, with 20, has more.
Kristof Milak followed up his win in the 100 butterfly, where he lowered his own world record, by adding the 200 title. The Hungarian swimmer delighted the home fans as he finished in 50.14 ahead of Japan's Naoki Mizunuma and Canada's Josh Liendo.
Milak joined Phelps and South African Chad Le Clos as the only male swimmers to achieve the 100/200 butterfly double at a single worlds.
After five silver medals, Australia's Kaylee McKeown finally claimed a gold when she edged American Phoebe Bacon by four-hundredths of a second in the women's 200 backstroke. Bacon's teammate, Rhyan White, was third for her first medal at a worlds.
It was the closest result in this race at a worlds since 1986, when East Germany's Cornelia Sirch was two-hundredths of a second ahead of American Besty Mitchell. Sirch later suffered health problems that she attributed to her country's state doping program.
With one day of racing remaining at Duna Arena, the United States has 37 medals, one short of the record 38 it claimed the last time Budapest hosted the worlds in 2017.