GWANGJU • Teenager Ariarne Titmus yesterday shocked reigning Olympic champion Katie Ledecky by winning the 400m freestyle title at the Fina World Championships in Gwangju, South Korea.
The 18-year-old Australian came home in 3min 58.76sec, ahead of Ledecky (3:59.97), who had been gunning for a fourth straight world crown in the event, with fellow American Leah Smith third (4:01.29).
This was the five-time gold medallist's first loss in the 400m and she later admitted the defeat "stings a little, (it's) unfamiliar and different".
Ledecky, who had not lost in the 400m since 2012, told NBC Sports: "I just got to the last turn and felt like I just tightened up. My legs were just dead. Obviously, Ariarne took advantage of that.
"I knew it was going to be a tough race going in. I was nervous for it. I need to rebound from this, and I need to get my fight back."
Titmus, whose nickname is the "Terminator", will now be the favourite for Wednesday's 200m free, and she revealed to news.com.au that she "knew that I properly had that in me".
The reigning Commonwealth Games 400m free champion said: "I feel pretty normal, it was just a swimming race. I just wanted to fight as hard as I could."
Separately, Adam Peaty became the first to swim the 100m breaststroke in under 57 seconds yesterday, setting a world record of 56.88sec in the semi-finals.
The reigning Olympic champion, who is unbeaten in the event over the last five years at major championships, lowered his own mark of 57.10sec set last year.
"There's no other word except for 'incredible'," he said. "I've been chasing that for three years now, ever since I touched that wall in Rio (2016 Games), I was like, 'I could go faster'."
The 24-year-old Briton, who has pushed closer and closer to the 57sec mark over the last couple of years as he tried to fulfil "Project 56", will look to pick up his third straight gold medal in the event in today's final.
Also, Sun Yang captured a record fourth 400m free world title in an acrimonious final that was capped by rival Mack Horton's refusal to join him on the podium. The Chinese clocked 3:42.44, with the Australian taking silver in 3:43.17.
Sun later claimed he did not care if "not everyone likes me".
AGENCE FRANCE-PRESSE, REUTERS