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Ariarne Titmus has broken the women's 400 metres freestyle world record at the Australian championships.
Titmus clocked three minutes 56.40 seconds in Sunday night's final in Adelaide.
Her time bettered the previous benchmark of 3:56.46 set by her American rival Katie Ledecky at the 2016 Olympics.
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"It's kind of nice now that I am not going to be asked when I am going to break the world record," Titmus said.
"I am the happiest I have ever been outside of swimming, I am the happiest I have ever been in my life in swimming.
"It's definitely showing in the pool."
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Titmus beat Ledecky for Olympic gold in the 400m and 200 freestyle and finished behind the American great in the 800m freestyle final at last year's Tokyo Games.
"I am definitely not putting the pressure on myself that I used to but it's still a healthy amount," the 21-year-old said.
"That has been the trick to me swimming well.
"Just going out there completely fearless, swimming what I used to feel like when I was 16 and first cracked on to the national team and just going there and surprising myself."