Australian swimming star Ariarne Titmus has gone sub four minutes in the 400m freestyle at the National Championships on Thursday night.
It was just the second time in her career the Tasmanian-born swimmer had equaled her Commonwealth and Australian record of 3:59.66.
Titmus lead the entire race and touched the wall almost 12 seconds ahead of second-placed Mikayla Messer (4:11.91).
"That is pretty crazy to match it," Titmus told media after the race.
"I tried to do the best I can out there by myself, it's a lot tougher.
"As much as I tried my hardest tonight, you can always think if you did have someone there, what would happen."
Earlier this week, Titmus set a new Commonwealth record in the 200m freestyle with a time of one minute 54.30 seconds, which is more than half-a-second inside the previous Commonwealth benchmark.
Australia's 2019 World Championship team for Gwangju in July will be decided at a selection meet in Brisbane a month beforehand.
At the World Champs, she will come up against Olympic Champion and World Record holder in the 400m and 800m Katie Ledecky.