Olympic champion Ariarne Titmus says teenage Canadian rival Summer McIntosh is yet to prove herself under pressure, as the pair ready for a blockbuster showdown at the world swimming championships next month.
The Australian, who stunned American great Katie Ledecky to win the 200m and 400m freestyle double at the Tokyo Olympics, had her 400m world record snatched away by 16-year-old McIntosh in March.
McIntosh's stunning 3:56.08 swim at the Canadian trials smashed the previous record of 3:56.40.
That was set by Titmus last year when she shattered Ledecky's six-year-old mark of 3:56.46 at the 2016 Rio Olympics.
All three are set to suit up for one of the most anticipated races of the July world championships in Fukuoka, Japan.
Titmus, who on Tuesday easily qualified at the Australian trials in 3:58.47 -- the year's second-fastest time behind the Canadian -- said McIntosh still had plenty to prove.
"On paper I'd say I'm still Olympic champ going in," she told reporters in Melbourne.
"I feel like Katie, Summer and I are quite even going in, to be honest.
"But I feel like with the experience that Katie has had, and with what I have had, we have had more experience than Summer racing with the pressure.
"I feel like Summer hasn't really had that experience yet, racing on the international stage with the big pressure, so it'll be interesting to see how she goes," she added.
And Titmus, who is also set to swim the 200m and 800m freestyle in Japan, warned that seeing her world record broken had only given her more motivation.
"World records are obviously there to be broken. But when you do break one, you kind of naively think that they might last forever," she said.
"So when it did get broken, it was a bit of a bee sting, 'oh, OK the world of swimming is moving'.
"So it does kind of add that little bit of extra motivation because everyone's always getting faster."
Defending her crown at the Paris Olympics is Titmus's ultimate goal, after which she will consider her future.
"I plan to continue swimming, but I can't think beyond (Paris). It's too overwhelming," said the 22-year-old.