MELBOURNE (Reuters) - Australia's Ariarne Titmus says Katie Ledecky is "100% still favourite" to win the 400 metres freestyle gold at the Tokyo Olympics despite upsetting the American world record holder at Gwangju last year.
The teenager ended Ledecky's six-year unbeaten run at world championships with a swim of three minutes 58.76 seconds in the 400 final, a full second quicker than the American.
While thrilled with the unexpected triumph, Titmus still feels she is "chasing" Ledecky, who holds the Olympic titles in the 200, 400 and 800m freestyle.
“Her world record (3:56.46) is still two seconds over my PB (personal best)," Titmus said in comments published by News Ltd media on Tuesday.
"I am just glad I had a great swim at worlds and she had an off-swim.
"She is 100% still favourite."
Titmus, 19, said the pace of her development as a swimmer had been a surprise and that she had never imagined topping Ledecky in South Korea.
"I did not think it would come this soon, but based on how I was swimming, I knew this was the time I would have a proper race with her and not just be racing for silver.
"I knew it was going to be a battle but did not know that would mean actually beating Ledecky."
The Tasmanian will also be looking to medal in the 200 and 800 freestyle at Tokyo.
She grabbed the world silver behind Italy's Federico Pellegrini in the 200 and took bronze in the 800 behind Ledecky and Italian runner-up Simona Quadarella.