The penny has finally dropped for Olympic champion Mack Horton – he can no longer keep swimming his beloved 1500m freestyle.
After being "in denial" ahead of the Gold Coast Commonwealth Games, Horton realised the awful truth when he collected 1500m bronze on Tuesday night.
"It's a sad day," Horton said.
"I still love it (1500m) but my focus is going to shift."
Horton had held on to hope that he could keep his prized event in his huge program despite the 800m freestyle being introduced at Tokyo 2020.
Despite winning Rio 400m freestyle gold, Horton had always considered himself a 1500m man after worshipping Grant Hackett as a kid.
Growing up, he had even kept a list of the all-time 1500m times on his bedroom wall dreaming of one day joining them – or even topping it.
But Horton said his body was telling him he would never add to Australia's rich history in the event.
It hurt to say it but Horton conceded he would now only pursue the 200m-400m-800m treble at Tokyo.
"I have been in denial about the 800m," he said.
"I think my body is telling me that is where it needs to be.
"I think (coach) Craig (Jackson) has known for a while but he wanted me to figure it out. I think I have figured it out now."
Horton looked on track to push his great mate, Italian distance king Greg Paltrinieri, in the 1500m at Tokyo after collecting bronze at the 2017 world titles.
Horton had also finished fifth in the Rio 1500m final.
But Horton said there was no denying what his body was telling him after Australia's Jack McLoughlin claimed Commonwealth 1500m gold.
"I wasn't sure where my body was at but we now know we have to shake things up a bit with my program," Horton said.