Australian Olympic champion Zac Stubblety-Cook booked his spot in the semi-finals of the 200m backstroke after giving fans and commentators a “heart attack” with a wild swim.
On a night where Aussie big guns Kyle Chalmers, Mollie O’Callaghan and Shayna Jack all progressed in their 100m heats, there was genuine concern Stubblety-Cook would have been a shock omission.
Stubblety-Cook, who won gold in this event in Tokyo, started extremely slowly and looked like bombing out when he was at the back of the field at the final turn.
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But the 25-year-old produced a stunning final 50m to motor past the field and incredibly take the victory.
“Talk about giving us a heart attack,” Giaan Rooney said in commentary.
A relieved Stubblety-Cook said he may have “left my run a little bit late” after the race.
Earlier, Australian superstar Chalmers has sent an ominous warning to his 100m rivals with a blistering performance in his heat on Tuesday night.
Swimming in the 10th heat alongside world record holder Zhanle Pan, Chalmers produced a brilliant 48.07 to win his heat ahead of German Josha Salchow.
Australian great Ian Thorpe predicted Chalmers could improve by up to a second in the semi-final and final.
Pan was back in fifth, but did enough to just scrape through to the next round.
Aussie William Yang was just behind Pan, but cruelly missed out on a spot in the semi-finals by just 0.05s.
While Chalmers won his heat, he was only sixth-fastest overall.
American Jack Alexy topped the leaderboard with a time of 47.57, just ahead of hometown favourite Maxime Grousset (47.70).
Chalmers, who won the event in 2016 in Rio and finished second in Tokyo, has previously said this will be his last Olympics.
Fresh off her gold medal in the 200m freestyle, O’Callaghan went head-to-head with Jack in a blockbuster heat.
The Aussie pair started slowly, but stormed home to take the top spots.
O’Callaghan posted a time of 53.27, while Jack was 53.40.
Jack is making her first appearance at the Olympics, having fought back from mental health struggles while battling to clear her name after testing positive for a banned substance that resulted in a two-year ban.
Meanwhile, Moesha Johnson qualified for the final of 1500m with a time of 16:04.02.
The Aussie was fourth in her heat, but it was still enough to get through with the fifth-best time.
Compatriot Lani Pallister had earlier withdrawn from the heats after testing positive for COVID.
American superstar Katie Ledecky was comfortably the fastest qualifier and appears certain to add another gold to her impressive haul.
Finally, Australia’s male 4x200m relay team qualified for the final and Matthew Temple missed out on a spot in the semi-finals of the 200m butterfly.