Pop star turned Olympic swim hopeful Cody Simpson MISSES first chance to secure a spot in Dolphins squad ahead of Paris Games

Former global pop star turned swimmer Cody Simpson has failed in his bold bid to become an Olympian.

Simpson, 27, who returned to the pool four years ago, has missed a spot in the men's 100m freestyle final at Australia's selection trials in Brisbane.

Kyle Chalmers, the Olympic champion in the event in 2016 and silver medallist at the Tokyo Games of 2021, topped qualifying times - but then declared he partly botched the race.

Simpson ranked 10th in the heats with a time of 49.04 seconds. The eighth quickest, Max Giuliani, secured a spot in the final by clocking 48.90.

The 27-year-old, who hit pause on his pop career to return to swimming, has one more chance to make Australia's swim team for next month's Paris Olympics.

Simpson will race his preferred 100m butterfly on Saturday.

'It's a stacked field in the 100 free so I knew it was going to be a bit iffy trying to get in to that final,' he said.

'It's a good warm-up for the 100 fly. 'I have had a really good last six months of training just absolutely flogging myself.

'Swimming is tricky....you're training for a long time for really marginal gains, microscopic sometimes.

'I have just been banging at the brick wall trying to get to that next level. And the faster you get, the harder it is to keep getting faster.'

Chalmers touched in 48.39 ahead of William Yang (48.50) and Flynn Southam (48.64).

'I probably didn't execute to the best of my ability...there are definitely some areas I can improve on,' he said, looking forward to the final.

'I will really put the pressure on myself....it has got to be self-driven and self-motivated.'

Elsewhere, Kaylee McKeown topped the times in the 200m backstroke heats.

The reigning Olympic champion and world-record holder in the event finished in two minutes 08.83 seconds with Hannah Fredericks (2:10.19) the next fastest.