Australia heads into Wednesday morning’s day four swimming finals with three medal chances after a strong Tuesday night session of heats.

Tokyo gold medallist Zac Stubblety-Cook gave Australians a scare, looking to be in serious trouble in his 200m breaststroke heat before surging from sixth to first in the final stretch.

“He looked like he was nearly gone,” Mat Thompson said in commentary, while Ian Thorpe even admitted it was a “risk”.

“I think I left my run a little bit late but good to get the win,” he said after the heat.

It isn’t anything new for Stubblety-Cook, who won the 200m breaststroke final at the Commonwealth Games in 2022 despite only taking the lead midway through the final lap.

Stubblety-Cook has mastered the art of conserving energy in the front end to finish faster and on top of the rest of the pack and that was the case on Tuesday night, even if it kept everyone on the edge of their seat, including Giaan Rooney.

“Even for Zac that was too comfortable,” she said in commentary.

“That first 100 was too cruisy… talk about trusting the process.”

Stubblety-Cook qualified second fastest for the semi-final while Australia’s Joshua Yong also made the cut with a time of 2:10.68.

Swimming in the second heat, Australia’s men’s 4 x 200m freestyle relay squad did its best to keep up with the British (7:05.11) but the combination of Kai Taylor, Zac Incerti, Flynn Southam and Tommy Neill finished second in a time of 7:05.63, good enough for 4th-fastest overall as they head into the final.

A big anchor leg from Neill, as the fourth Brit switched off, saw the margin slashed from a few metres to less than a body length in the final stages. Neill and Southam both posted times in the 1:45s, with Taylor and Incerti in the 1:47s.

The top four qualifiers were split by just 0.52 seconds with the USA and France, from heat one, in between the Brits and the Aussies. Remarkably Japan and Israel tied for eighth requiring a swim-off for a spot in the final.

“I’ve never seen that before!” Ian Thorpe proclaimed.

Elsewhere, Mollie O’Callaghan and Shayna Jack, having already teamed up for gold in the 4x100m women’s freestyle team, finished first and second in their women’s 100m freestyle heat to cruise through to the semis.

O’Callaghan finished with a time of 53.27 (fifth-fastest overall) while Jack came in second in the heat at 53.40 (sixth fastest).

Speaking on Channel Nine’s commentary, Giaan Rooney described it as a “very comfortable” swim from both women, adding that she believes O’Callaghan has “a lot left in the tank”.

After O’Callaghan claimed a second gold in Paris by beating Ariarne Titmus in Tuesday morning’s 200m freestyle final, ‘The Missile’ James Magnussen predicted she would add to her tally in the 100m.

Not only that – but Magnussen believes she’ll soon overtake Emma McKeon’s six gold medals and become Australia’s all-time greatest Olympian.

“I’ll call it now Matty, O’Callaghan will go on to be our greatest Olympian in history and I think that was the monkey she needed to get off her back to go on to be our most successful Olympian ever,” Magnussen said on the Matty & The Missile podcast.