Sarah Sjoestroem cruised to her fifth consecutive World Aquatics Championships title in the women's 50 metres butterfly event on Saturday, before the evergreen Swede broke the world record in the semi-finals of the 50m freestyle race.
The 29-year-old finished the day's opening event in 24.77 seconds to deny China's Zhang Yufei, who was 0.28 seconds behind while Gretchen Walsh of the United States took bronze.
"That was amazing, I'm very proud of this gold which is the fifth one, it's amazing," said Sjoestroem, who also went level with American great Michael Phelps on 20 individual medals at the world championships.
"I feel like I enjoy it more than ever at the moment."
Sjoestroem then produced a superb effort of 23.61 seconds in the freestyle 20 minutes later to eclipse her own mark of 23.67 seconds which she had set in the 2017 worlds in Budapest.
American Katie Ledecky showed she was also at the peak of her powers at the age of 26, going quickest in the women's 800m to retain her title and bag a 21st worlds gold overall having also won the 1,500m race this week.
"I've never even dreamt of even coming to meets like this, so to be here and to have been to a bunch of world championships is amazing," Ledecky said.
"I'm loving every second and trying to enjoy each moment. There are some really great competitors in there in all of my events. Kudos to them for pushing me all the way.
"It's always a battle, it's always a great race. So I know I have to bring my best every single time."
Ledecky led from start to finish and touched the wall in 8:08.87, four seconds outside of her 2016 world record. She went 4.44 seconds faster than silver medallist Li Bingjie of China, with Australia's Ariarne Titmus collecting bronze.
Victory also meant Ledecky surpassed Phelps' record tally of 15 individual gold at the worlds. Her sixth 800m freestyle gold was another new mark, with no swimmer achieving the feat in a single event at the worlds.
MEMORABLE TREBLE
Australia's Olympic and world champion Kaylee McKeown sealed a memorable treble at the meet as she roared to the women's 200m backstroke title after the 22-year-old had prevailed over 50m and 100m earlier in the week.
McKeown, who also holds the 200m world record, finished in 2:03.85 to beat American Regan Smith who finished more than a second behind despite leading early on in the race.
"That means a lot. I didn't think I'd be able to do that tonight, especially after a long week," an exhausted McKeown said of her treble.
"That's the best thing about sport, you have to focus on your own race, and that is exactly what I did tonight."
China continued their good showing at the worlds as Peng Xuwei took bronze at the Marine Messe Hall.
The absence of 2022 men's 100m butterfly champion Kristof Milak and Olympic gold medallist and world record holder Caeleb Dressel added a dash of uncertainty to the final as American Dara Rose dominated the semi-finals.
But it was Frenchman Maxime Grousset who came home in 50.14 seconds to take the gold ahead of Canada's Josh Liendo and Rose. It was France's fourth gold of the meet, with Leon Marchand grabbing the other three.
Australia's Cameron McEvoy won the men's 50m freestyle gold in 21.06 seconds, outclassing silver medallist Jack Alexy of the U.S. by 0.51 seconds. Briton Benjamin Proud settled for bronze.
The Australian mixed 4x100m freestyle relay team of Jack Cartwright, Kyle Chalmers, Shayna Jack and Mollie O'Callaghan lowered their world record in the last race of the evening as they finished in 3:18.83.
It was a brilliant day for Lithuania's Ruta Meilutyte, who matched Italian Benedetta Pilato's 2021 50m breaststroke world record of 29.30 seconds in her semi-final and will go into Sunday's final seeking a second gold at the meet.
Australia lead the medal table with 13 golds before the final day's action, where seven titles will be up for grabs.
China are second with five golds, ahead of the U.S. and France on four each.
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