Tasmanian swimming sensation Ariarne Titmus has secured a national championship treble after bolting to a commanding win in the women's 400m freestyle on Thursday night.
The 18-year-old former Launceston Aquatic member swum 3:59.66 to match her time from last year's silver medal effort at the Pan Pacific swimming championships, adding to her 200m and 800m freestyle titles from earlier in the week.
One of only three women ever to have swum 400m in less than four minutes, Titmus led from start to finish to win by more than 12 seconds at South Australia's Aquatic and Leisure Centre.
"It feels pretty good, coming into this week I've been training really well and to come in and do times like this in a really tough block is really exciting," Titmus told Seven post-race.
"It's a bit more tricky, I had to try and think about what the race felt like when I was up against [world champion Katie Ledecky] last year and try and get that feeling.
"I know in the second half of the race last year I could see her and that gave me a bit more of a push.
"I had to try and think what that felt like and I think I did pretty well tonight."
Earlier in the night, South Esk swimmer Morgen Hawkins recorded a fifth-place finish in the women's 50m breaststroke final.
The 21-year-old Tasmanian record holder started slowly before pushing for a podium spot late, finishing 0.23 of a second off third spot in 32.27.