The golden girl has regained her Midas touch by clocking one minute, 54.55 seconds to upset Ariarne Titmus in the 200m freestyle final at the world titles trials in Brisbane on Tuesday night.

It was not only a personal best time, but also the fastest she had gone over 200m since the 2016 Rio Olympic trials.

The scorching time rocketed her to the world No.2 ranking just five weeks ahead of the world titles in South Korea.

But it did so much more for her self confidence.

At 25, McKeon had begun to think her days of being a 200m threat were over after being hampered by a shoulder injury in early 2018.

McKeon won bronze in the 200m in Rio, and shared silver with US great Katie Ledecky in the four-lap event at the 2017 world titles.

However, the shoulder niggle had evaporated her self belief - until now.

"That gives me a lot of confidence. I kind of lost a bit of confidence over the last few years since Budapest (2017 world titles) after I hurt my shoulder," McKeon said.

"But I have been working a lot more on the mental side of things.

"I realise as you get older you don't have the same body, the body doesn't work exactly the same way.

"So I have to work on the mental side to make improvements."

McKeon is now daring to dream of challenging a formidable 200m field at next month's world titles in Gwangju, South Korea featuring Titmus, Ledecky and Swedish powerhouse Sarah Sjostrom.

She finished as Australia's highest medal-winner at the Rio Olympics, with the 200m freestyle bronze, gold in the 4x100m freestyle relay and two silver relay medals.

Titmus, 18, was the overwhelming 200m favourite after setting a new Commonwealth record at April's national titles.

The teenager was also contesting her first race since breaking the 400m freestyle Commonwealth record at the six day trials' opening night on Sunday.

But Titmus could not overcome McKeon's blistering start.

Titmus believed she would only benefit from McKeon's renewed challenge before lining up in what will be a much anticipated 200m event in South Korea.

"Emma is a world class swimmer and I am glad that I can race her at home," Titmus said.

"Not many have the opportunity to race one of their main competitors domestically - it is great for both of us."

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