Olympic 200m breaststroke champion Zac Stubblety-Cook smashed the world record Thursday at the Australian championships, touching in 2mins 05.95secs to send a warning for the world championships and Commonwealth Games.
The 23-year-old was under the record pace for the entire race to shatter the 2:06.12 mark set by Russia's Anton Chupkov in 2019.
"I was just trying to swim fast -- I didn't think that fast. I can't really believe it to be honest, but I'm very happy with that," he said poolside in Adelaide.
"Last year I put everything in and got that result (Olympic gold), but this year there's a lot less pressure and obviously that pressure is nice not to have, and I'm just stoked."
Stubblety-Cook swam a blistering race to stun the field and win gold in Tokyo last year in a new Olympic record time of 2min 06.38sec ahead of Dutch ace Arno Kamminga.
The Australian will now head to the worlds in Budapest next month and the Commonwealth Games in Birmingham in July as red-hot favourite.
"The end goal is Paris (2024 Olympics) and whatever happens in between I'm just going to enjoy my swimming," he said.
Asked if it was the perfect race, he replied: "I think there's always room to improve."
Stubblety-Cook became the only Australian man to hold a current long-course world record. Kaylee McKeown owns the women's 100m backstroke world record.
Tokyo sensation McKeown, who won the Olympic backstroke double, also fired a warning to her rivals with the fastest time of the year in the 400m medley.
She has added the format this year after dropping it for the Olympics and touched in 4:31.74, more than three seconds quicker than Canada's Summer Mcintosh.
SIMPSON DOUBT
Kyle Chalmers could ruin pop star Cody Simpson's dream of swimming at the worlds after indicating he may change his mind and compete in the event.
Chalmers, who won 100m freestyle silver at the Tokyo Olympics and gold in 2016 at Rio, had been adamant he would not be in Budapest next month.
But after winning the 50m butterfly in Adelaide in a competitive 23.21 secs Thursday and finishing second behind Matt Temple in the 100m fly, he is having second thoughts.
"Eight weeks ago I didn't know if I would be swimming at all this year so it would have been disrespectful of me to say I was going to the worlds," he said.
"I'll have a conversation with my coach .. I'd love to be part of the team. I've earned my spot on the team now and we'll see what happens over the next little period."
Only the top two qualify for the world championships.
Simpson, who has made three music albums and worked with Justin Bieber and dated Miley Cyrus, came third in the 100m fly and thought he had done enough, thinking Chalmers would be a no-show for Budapest.
Whatever happens, Simpson will swim at the Commonwealth Games with the top three qualifying for that event.
Elijah Winnington ensured he will race both the 200m and 400m free in Budapest and Birmingham after coming second over the shorter distance, edged by Zac Incerti (1:45.80).
Dual Olympian Brianna Throssell won the women's 100m fly title in 57.31 in the absence of seven-time Tokyo Olympic medallist Emma McKeon.
Chelsea Hodges claimed the 50m breaststroke in 30.15 while Mollie O'Callaghan (27.46) took out the 50m backstroke.