The Dolphins now have as many gold medals as the famous Australian team of 2001 - featuring the likes Ian Thorpe, Grant Hackett and Petria Thomas - that came to this city and created a legacy that lasted decades.

With seven gold medals up for grabs on the final day of competition on Sunday, Australia cannot be knocked off top spot on the medal table. China (five gold), USA (four) and France (four) are below Australia.

It is just the second time since the Melbourne 1956 Olympics that Australia will beat the USA on a medal tally at a major international swimming meeting.

As far as stories go among this all-conquering Australian team, McEvoy’s gold medal is about as good as it gets, in terms of swims that no one could have forecast 12 months ago.

At the Tokyo Olympics, McEvoy finished 29th in the 50m freestyle and 24th in the 100m freestyle.

He thought his time was done. Last year, McEvoy did not swim a single competitive race last year.

Let that sink in.

McEvoy hit the gym. Not as an athlete, but just like anyone else at their local gym. Finally, he was free to do whatever he wanted.

He had a change of heart and started again. He revolutionised his training program, opting for more strength work instead of the same repetitive sets that failed to yield any significant improvements to his times.

With an extra 10 kilograms of muscle and surrounded by biomechanists and nutritionists at the Queensland Academy of Sport, with the guidance of coach Tim Lane, McEvoy took the swimming world by storm when he clocked 21.27 seconds in the 50m freestyle at the Australian trials last month.

Before his final on Saturday, McEvoy went for a coffee with his girlfriend. The magnitude of what he might be about to accomplish hit McEvoy all at once.

“There was probably three or four times today when I almost had tears come up … just out of being so proud of being in this position,” McEvoy said.

“I have rejuvenated motivation. I’ve got a new approach which I’m really excited to fully flesh out. I’ve only been doing it for nine months. I just want to get back in the water next week. My last individual [world championship] medal was in 2015. It’s been a long time between drinks. It’s really satisfying. I have a ton of ideas. It’s been so long since I’ve been in form.”

As McEvoy recounted his remarkable return to the pool on live television, McKeown (2:03.85) edged out Regan Smith (2:04.94) to become the first person in history to win the 50m, 100m and 200m backstroke treble.

McKeown, the world record holder in the event, had so little in the tank after her race that she didn’t even get to the warm-down pool like she had planned.

“I just sat down and gathered myself. I was pretty gassed after that. I’m really happy with that.”

Australia (3:18.83) won their mixed relay by 1.99 seconds as O’Callaghan brought the victory home with another fine anchor leg to claim her fifth gold medal of a sensational world championships.

If O’Callaghan can win gold in Sunday’s women’s 4x100m medley relay, she will equal Ian Thorpe for the most gold medals won at a single world championships.

“That’s a lot of pressure,” O’Callaghan said with a grin. “I’m just taking it day by day.”

Ariarne Titmus added to her gold medal in the 400m freestyle and silver medal in the 200m freestyle by picking up a bronze in an 800m freestyle final that Katie Ledecky won in a time of 8:08.87.

The Australian equalled her personal best (8:13.59) that she did in Birmingham last year at the Commonwealth Games.

“I’m just excited to sit in the stands and cheer tomorrow,” Titmus said. “I’m looking forward to a sleep-in and maybe some chocolate.”

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