Elijah Winnington has produced a beautifully timed swim to take gold in the world short course championships at the same Budapest venue where he first made his name as a Dolphins' powerhouse.

Two years since he lifted the equivalent long course title in the Hungarian venue, Winnington roared through over the last six laps of the 25m pool on Thursday to take another gold in the 400m freestyle.

It was Australia's second title of the championships after Lani Pallister's gold in the 800m freestyle, and an emotional one for the 24-year-old Queenslander Winnington, who had won silver at the Olympics earlier in the year.

Still more than half a second behind American Kieran Smith with 75m left, Winnington only got on terms on the penultimate lap, and from there, he was never going to be stopped as he raced home in 3 minutes 35.89 seconds, 0.42 seconds clear of another American Carson Foster with Smith eventually third in 3:36.31.

"This pool holds a special place in my heart. I won my first world title in this pool, and I'm glad to do it again," said Winnington, telling the crowd they were "amazing".

"I kind of didn't see him (Smith, on the inside lane) until about the 250m mark, and I thought, 'uh-oh!'

"But I knew he would be fast — he's the reigning world champ in that event from Melbourne — and my strategy is always to come home strong and just fight until the end.

"I'm probably not in my fittest state right now, so I just knew it'd be a race and I had to stick with him — and I know I'd have the biggest heart coming home."

Winnington's triumph was the highlight of another fine day for the Dolphins, with Lizzie Dekkers having earlier taken bronze in a support act to another world record-breaking tour de force from Canadian Summer McIntosh in the 200m butterfly.

Olympic and world champion McIntosh, just 18, took the title in 1:59.32, beating American Regan Smith (2:01.00) while Dekkers was timed at 2:02.91.

McIntosh eclipsed Spaniard Mireia Belmonte Garcia's 10-year-old record of 1:59.61, following up her landmark 3:50.25 in the women's 400m freestyle on Tuesday. For good measure, she also set a new world junior record 2:01.96 to win her morning heat.

In the day's final event, Dekkers medalled again and Pallister won her fourth gong of the championships with a stirring anchor leg as the women's 4 x 200m relay quartet that also featured Leah Neale and Milla Jansen took bronze behind a world record-breaking US foursome.

Alex Walsh, Paige Madden, Katie Grimes and Claire Weinstein clocked the new mark of 7:30.13, with Hungary runners-up in 7:33.39 and the Aussie quartet just falling short of the silver in 7:33.60.

In the medal table, Australia are now third (2 gold, 2 silver, 3 bronze), behind Canada (3 gold, 2 silver, 4 bronze) and a rampant USA outfit, who have 18 medals in total (9 gold, 6 silver, 3 bronze).

AAP