Simpson also found a partner through his swimming journey, striking up a relationship with Olympic great Emma McKeon and making it public in 2022.

Now Simpson has penned a note to his 5.1 million Instagram followers declaring his swimming journey has ended, signing off with a thank you to the sport he adored as a child and rediscovered in his 20s.

“All you can do is everything you can to take what you’ve been given as far as you can take it,” he wrote in part.

“I left nothing to the unknown these past four years and I can now rest knowing I put my pedal to the floor every day and covered every other little detail to take this as far as it could go and it sure went a hell of a ways.

“I’m grateful for a huge run in the short amount of time I have been a professional athlete and I wouldn’t trade a moment.

“I promise I will never stop trying to do special things with my life. Shoot for the moon … land among the stars.

“My shot has landed me in a constellation of stars otherwise known as that elusive club, the Australian Swim Team, forever. Thank you swimming.”

All eyes were on the popstar in the men’s 100m butterfly final on Saturday in his final shot to make the team and he was in the hunt coming down the last lap.

You could have thrown a blanket over the field and Simpson ultimately finished fifth in 51.79 — just outside his personal best of 51.67 and 0.01 slower than his heat swim.

National record holder Matt Temple won in 51.15 ahead of Ben Armbruster, who had already qualified in the 50m freestyle.

Shaun Champion (51.40) was third and Jesse Coleman (51.51) fourth.

Simpson had earlier tied first in the 100m freestyle B final in 48.67sec, which was good enough for equal sixth overall.

It would have given selectors food for thought about picking him as a 4x100m freestyle relay swimmer, but it didn’t count for much because he didn’t do it in the A final.

He had already surpassed expectations after making the 100m butterfly final at the Tokyo Olympic trials and earning a spot on the Australian team for the 2022 Commonwealth Games.

He finished fifth in the 100m butterfly in Birmingham, where he also won those gold and silver medals as a relay swimmer.

But Australia’s depth in the 100m fly has strengthened and Olympic qualification ultimately proved a bridge too far.

“It’s bittersweet. I did what I could do,” a philosophical Simpson told reporters afterwards.

“I’ve come a lot further in the last four years than I perhaps could have bargained for.

“(I) started from zero and tried to see how far I could get with a half or a third of the time everybody else has been training … just to do right by that kid in me who gave it up to go and pursue something else, which I had an incredible journey in.

“(I) wanted to come in these last four years and have a real good go.

“To have had the chance to swim for my country and make Australian teams, medal internationally and be a part of the men’s relay and swim for Australia is something not a lot of swimmers get to achieve or experience. I have had the privilege to do that.

“That’s something I’ll never forget and nobody will be able to take from me.

“I feel really proud to see how far I could go and satisfy the fire that was inside me and compete again and push myself in training.”