French hero Leon Marchand and Canadian prodigy Summer McIntosh headline as swimming's world championships begin in Singapore on Sunday with thoughts already turning towards the 2028 Los Angeles Olympics.
Marchand is appearing at his first major competition since rocketing to global fame at last year's Paris Games, where he won four golds in front of an adoring home crowd and lived up to his billing as the next Michael Phelps.
The 23-year-old skipped the world short course championships in Budapest in December, saying he was "exhausted" after his Olympic exertions.
He returned to action in May and will concentrate on the individual medley events in Singapore.
Having broken Phelps's 400m medley world record at the world championships in Japan two years ago, Marchand now has his sights set on Ryan Lochte's long-standing 200m medley mark.
"He wants to see what happens in the 200m medley, without having any other races on his plate," Marchand's club president in Toulouse, Michel Coloma, told AFP.
MCINTOSH ON FIRE
While Marchand is still feeling his way back to action after his Olympic heroics, McIntosh heads to Singapore in red-hot form.
The 18-year-old broke three world records in a matter of days at the Canadian trials last month, including Hungarian great Katinka Hosszu's decade-old 200m medley mark.
It was the first time any swimmer had broken three different long course world records at one meet since Phelps at the 2008 Beijing Olympics.
McIntosh won three gold medals at the Paris Games and said she was "super pumped" after her scintillating start to 2025.
"I think the goal is always to be faster and that's how I approach every day in training," warned McIntosh, who is set to compete in five individual events in Singapore.
McIntosh smashed Australian Ariarne Titmus's 400m freestyle world record but the pair will not go head to head in Singapore, with Titmus taking time off before she prepares for the LA Games.
Several other leading swimmers are doing the same, with Britain's Adam Peaty, Sweden's Sarah Sjostrom and Hungary's Kristof Milak among those sitting out.
There will be no shortage of stars competing in Singapore, however, with American great Katie Ledecky high on the billing.
Ledecky has also broken a world record this year, updating her own 800m freestyle mark that had stood since the 2016 Rio Olympics.
The 28-year-old is competing at her seventh world championships and is looking to add to her collection of 21 gold medals.
"I have been to a lot of these but I still feel like I get the same excitement, the same energy from the team," she said.
Ledecky and McIntosh will clash in the 400m and 800m freestyle, with the latter race billed as the one to watch in Singapore.
The US team also features Gretchen Walsh, who lowered her own 100m butterfly world record twice in one day in May.
Bobby Finke, Torri Huske, Jack Alexy and Regan Smith also compete for the Americans.
PRE-TEEN PRODIGY
At the other end of the experience spectrum is 12-year-old Yu Zidi, who was picked by China after announcing herself in stunning fashion at her country's national championship.
Yu, sporting a cartoon dog on her swimming cap, qualified for three individual events and is part of a Chinese team that also includes men's 100m freestyle world record holder Pan Zhanle and breaststroke contender Qin Haiyang.
China will be looking to finish high in the medal table but they will be hard pushed to break up the battle for top spot between the United States and Australia.
The Australians might be missing Titmus but Olympic champions Kaylee McKeown, Mollie O'Callaghan and Cam McEvoy should ensure they bring home plenty of gold.
The Australian squad also features several new faces, including 16-year-old Sienna Toohey.
Head coach Rohan Taylor called Singapore crucial experience for the 2028 Olympics.
"The end goal is LA, but to be great in LA this very young team, which boasts 10 rookies, is going to learn what is needed on the global stage in Singapore," Taylor said.
Olympic champions David Popovici of Romania, Germany's Lukas Maertens and Italy's Thomas Ceccon are all also in action.