Lani Pallister’s gold rush has continued, anchoring Australia to a relay world record to win her third gold medal of the world short course championships in Melbourne.

The 20-year-old won gold in the 800m after opening the championships with a 400m victory, and she was able to back up on Wednesday with a stunning final leg in the 4x200m freestyle relay to steer the home team to a record-breaking victory.

It comes after the Australian women also smashed the world record in the 4x100m freestyle relay 24 hours earlier.

They were also able to do it without superstar Emma McKeon, who opted not to race the 200m relay to concentrate on her individual program.

Madi Wilson led the team out, handing over to Mollie O’Callaghan, who had battled agonising cramps before the race after winning a silver medal in the 100m backstroke.

Leah Neale kept the Australians in front through the third leg before Pallister secured the gold with the fastest split, powering them to finish in 7 minutes 30.87 seconds, eclipsing the Dutch mark of 7:32.85 set in 2014.

Canada were second in 7:34.47, ahead of the USA in 7:34.70.

Pallister said three gold medals in three events was a dream come true.

She still has the 1500m freestyle ahead.

“It’s the first time I’ve raced a 4x200m final so I really wanted to put my foot on the line and show the coaches who had faith in me I was able to do the job,” Pallister told reporters.

Four women in yellow smile and hold up gold medals
Gold medallists Madison Wilson, Leah Neale, Mollie O’Callaghan and Lani Pallister after breaking the record in the 4x200m freestyle relay.(Getty Images: Daniel Pockett)

“It’s such an incredible opportunity to race on home soil and come away with a world record.

“I’ve been doing a lot of work around backing up so I had long enough between the 800 and the relay to be able to recover and put up a performance like I did tonight.”

The daughter of former Australian distance swimming great Janelle Elford, Pallister took control of the 800m race from the get-go.

With four laps to go, her lead was out to half a pool length before she touched the wall in 8:04.07, which was 6.34 seconds ahead of the field.

It also beat her personal best by more than three seconds.

The Queenslander’s world championship success has come after she considered giving the sport up following heart surgery, as well as battling an eating disorder and glandular fever over the past two years.

Kaylee McKeown added another gold medal to the Dolphins’ haul, pipping teammate O’Callaghan to win the 100m backstroke.

World record holder in the long course 100m backstroke, McKeown, in lane seven, touched the wall in 55.49 seconds, with O’Callaghan taking silver with 55.62 and American Claire Curzan third.

The triple Olympic gold medallist needed a big finish to overhaul the field.

“I had a rough turn on the third 25 and I had to give it everything because I had a bit of catching up to do,” the 21-year-old said.

Teen Isaac Cooper, who was banished from the Commonwealth Games team for misusing prescription medication, won bronze in the men’s 100m backstroke behind American Ryan Murphy.

McKeon stamped her authority on the women’s 100m freestyle and will go into Thursday’s final as the fastest qualifier ahead of defending champion Siobhan Haughey, from Hong Kong.

In the men’s race, Australia’s world record holder Kyle Chalmers is ranked third with Jordan Crooks from the Cayman Islands the fastest in the semi-finals.

Romanian long-course world record holder, 18-year-old David Popovici, qualified fourth fastest.

In other results on Tuesday, American Torri Huske won the 50m butterfly and Brazilian Nicholas Santos took the men’s.