McKeown turned in the final 50 meters behind American Regan Smith, but pulled out the gold medal with a final run, touching the wall at 57.53, 00.25 seconds ahead of Smith (57.78). American Katharine Berkoff took the bronze medal with a time of 58.25.
The victory capped a 48-hour recovery for the Australian, who was left reeling after being disqualified in the women’s 200m medley on Sunday night.
However, the 22-year-old saw a bright side in the drama after winning her backstroke title.
“I’m sure there have been worse experiences, but that’s something I’ve learned, to not just get carried away and forget about it,” Nine said.
“It was 50-50 between the Americans and me, so it was great to be back in the last 50… I dug deep and gave it my all.”
McKeown admitted he was nervous before the race.
“I’ve never been so shaken in my life. I felt like I needed to throw up before I got my color,” he said.
“My old coach used to say that if you’re scared to the point it means you care about what you want to do, so I did my best.”
Australian swimming icon Ian Thorpe was full of praise for McKeown’s recovery from his failure in the medley semi final.
“It was different from the events that were disappointing,” he told Nine.
“To be able to make a play like this two days later shows the courage and determination that Kaylee McKeown has.
“He takes it with him and it’s his. It was until the last 15 meters.”
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McKeown is aiming to make it two golds later in the meet when he returns to the pool in the 200 meters backstroke, an event in which he is the reigning Olympic champion.
“My speed is there, whether my endurance is there or not, there’s something we need to know,” he said when asked about his hopes in the 200.
“We’ll see what happens.”
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