Competing in his new home of Tāmaki Makaurau, Olympian Lewis Clareburt showed his pedigree on day one of the World Championship Trials in Auckland.
A total of 272 swimmers are competing at the trials as they chase a spot in the Aquablacks squad for the 2024 World Aquatics Championships in Doha.
Despite having already qualified for Doha, Clareburt was all class in the 400m individual medley, powering ahead of the pack to finish in 4m 15.13s, more than 2 seconds under the 2024 World Championships qualification mark.
"I said to myself coming into this meet that if I go anywhere near under the qualifying time I'd be happy. It's been a tiring few weeks so I feel like that's a good time for me right now," Clareburt said.
Teen sensation Monique Wieruszowki continued her ascent by breaking her own national record in the 100m women's breaststroke.
The 16-year-old – who is relocating from New Plymouth to Auckland in search of better facilities – swam a time of 1m 08.68s, improving on the mark she set in April at the NZ Open Championships (1m 08.74).
Eve Thomas and Caitlin Deans were the other standout performers, both swimming under the Doha qualification time in a fast 400m freestyle race.
Thomas and Deans were a cut above from start to finish, clocking 4m 7.90s and 4m 10.42s respectively.
"I've come into this competition off some really intense pieces of work and haven't been doing anything particularly specific to prepare," Thomas said.
"That's the second fastest time I've ever done so I'm pretty stoked with that."
In the Para swimming Asher Smith-Franklin continued to improve, setting a New Zealand S14 record in the 100m butterfly of 1m 00.24s, as he inches closer to Paralympic qualification.
It was a case of almost but not quite in the rest of the day's racing.
In the men's 100m butterfly Cameron Gray finished just outside world championships qualification time in 53.02s.
It was a similar story in the women's 100m butterfly where Hazel Ouwehand led from start to finish, clocking a time of 58.94s, an agonising half a second out from the world championships qualification time.
Kane Follows was then in action in the 200m backstroke, posting a time of 1m 58.99s to miss qualification by less than a second.
Olympian Zac Reid then went close in the men's 400m freestyle, swimming a brilliant second 200m to finish less than a second outside the qualification mark in a time of 3m 48.92s.
Day two of competition will see Erika Fairweather's only event of the weekend as she works to help qualify a Women's 4 x 200m freestyle team.
The Men's 50m Freestyle will also be a fast one, with Cameron Gray and Carter Swift going head-to-head in a battle of the sprinters.
Gabi Fa'amausili will be hoping to return to the national team in the Women's 50m Backstroke, heading in as the fastest qualifier.
Five swimmers have already achieved qualification for Doha, following their performances earlier this year at the 2023 World Aquatics Championships in Fukuoka.
They are Clareburt, Fairweather, Andrew Jeffcoat, Caitlin Deans and Gray, with all except Jeffcoat competing this weekend.
RNZ/Newshub.
