Olympic gold medallist Alicia Coutts Saturday captured two national titles, while Christian Sprenger beat close rival Brenton Rickard, with all three securing places on the Australian team for the Barcelona world championship.
Coutts, a five-time medallist at last year's London Olympics, won the 100m butterfly in the Adelaide trials and set the world's best time this year in the 200m individual medley.
The 25-year-old, who almost gave up swimming after London, clocked 2:08.63 in the medley to boost her medal chances at the world championship in July.
She led home London teammate Emily Seebohm (2:11.11), with both swimming under the qualifying time and securing their places at the worlds.
Coutts earlier claimed the 100m butterfly to win a third consecutive national title, coming home in 57.18 ahead of Brittany Elmslie (58.02).
Sprenger held off Rickard to claim his third national title in the men's 100m breaststroke and book his place to Barcelona.
Sprenger, who was beaten for Olympic gold in the event by South African Cameron van der Burgh, was the favourite following excellent heat and semi-final swims and touched the wall ahead of national record holder Rickard in 59.31.
Rickard (1:00.00) also secured passage to Spain with second place.