Triple Olympic gold medallist Kaylee McKeown has narrowly missed breaking her own world record, thrashing the field in the women's 200m backstroke at the world championship trials.
And sprint king Kyle Chalmers lived up to his top billing in the men's 100m freestyle, winning in the second fastest time in the world this year.
McKeown clocked the fourth fastest time in history in Friday night's final in Melbourne, touching the wall in two minutes 3.70 seconds with the next swimmer Jenna Forrester almost seven seconds behind.
The Queenslander was on world record speed for the first three laps but couldn't keep the pace to top her previous best of 2:03.14, set at the NSW championships in March.
McKeown was thrilled with time at this point in her preparation for next month's world titles in Fukuoka, Japan.
"I probably went out a little bit too hard and didn't have my back end like I usually do but I'm super happy with the time," the 21-year-old said.
"... never in a million years would I have thought that I would have been able to go under 2:04 and I've done it twice now."
McKeown took both the 200m and 100m backstroke records from Regan Smith, and predicted the American would go close to taking them back next week at her own national trials.
"I can't put my feet up. I've got to train hard and race hard as I fully expect both world records to plummet, if not next week than at the world championships," she said.
"I think world records are there to be broken and it's just a matter of who can get up on the day and race the best because we're both phenomenal athletes.
"I've heard the stuff she does in training and it pushes me every day."
Rio Olympics champion Chalmers hit the wall in 47.44 seconds, while youngster Flynn Southam smashed his personal best to finish second in 47.77.
Chalmers, 24, almost left last year's Commonwealth Games after intense media speculation about his personal life but is now in a happy place.
"I'm having a lot of fun in the pool and a lot more fun out which I think is massively contributing to my success in the pool this year," he said.
"It's made me really enjoy the sport again and love it and probably rediscovered my passion and reason why I'm doing it."
Dual Olympian champion Ariarne Titmus qualified for her third individual event with victory in the women's 800m freestyle.
The 22-year-old, who won gold in the 200m and 400m and silver in the 800m in Tokyo, finished in 8:15.88 and clear of Lani Pallister, with both well within the qualification time.
Titmus won the 400m freestyle at the trials but was upset by Mollie O'Callaghan in the shorter distance.
"I wouldn't say I'm content with the swims this week but I think it's a bad thing to ever be content," she said.
"But job's done and I'm the plane and my focus now has to shift to worlds and I've got a lot of work to do before now and then."
Meanwhile, Thomas Neill finished right on Swimming Australia's qualifying mark in the men's 200m individual medley to book a seat to Japan.
Tokyo Olympian Neill clocked the exact qualification time of 1:57.74.
Elizabeth Dekkers is another to earn selection with an impressive performance in the women's 200m butterfly.
The 19-year-old's time of 2:05.26 was well inside the mark, as was second-placed Abbey Connor's.
