Abbey Harkin has opened her campaign at Australia's World Championship trials with a bronze medal in a tightly contested women's 100 metre breaststroke final.
The 21-year-old former Maitland schoolgirl, now with the St Peter's Western club in Queensland, finished within a second of Nunawading's Jess Hansen and Bond's Jenna Stauch in Brisbane on Monday.
Harkin stopped the clock at one minute and 7.93 seconds (1:07.93) with Hansen (1:07.06) and Stauch (1:07.93) slightly ahead.
All three swimmers missed the qualifying time (1:06.81) for South Korea next month.
In the men's 200m freestyle decider Newcastle's Thomas Fraser-Holmes finished sixth in a time of 1:47.64.
Olympic 100m gold medalist Kyle Chalmers (1:45.76) got the job done, but Rio Games 400m champion Mack Horton (1:47.05) missed the podium and the qualification mark of 1:46.28.
Mitch Larkin and Minna Atherton were the other two winners on Monday in the men's and women's 100m backstroke respectively.
On Sunday night, Hunter's Meg Bailey (2:14.39) was third in the women's 200m individual medley but outside the required 2:10.45.
Women's 200m freestyle and men's 200m butterfly finals are both on Tuesday.