The 40-year-old clocked a time of 58min 53sec to finish ahead of Great Britain’s Joseph Townsend, second in 60:43, and Germany’s Benjamin Lenatz, third in 68:11.

Joining Chaffey at Rio 2016 will be compatriots Brant Garvey, runner-up in the men’s PT2, and Kate Doughty, winner of the women’s PT4.

Garvey posted a time of 74:08 to sandwich himself between PT2 winner Andrew Lewis of Britain, who finished in 70:47, and third-placed Lionel Morales of Spain, who crossed the line in 74:54.

Doughty triumphed with a time of 72:10 as Britain’s Clare Cunningham came second in 74:21 and fellow Australian Claire McLean third in 1:15.47.

"It’s been quite a journey," Doughty, who has only been involved in the sport of triathlon for two years, told Australia’s Daily Telegraph.

"I guess it shows you should just never give up."

There were also victories for the hosts in the men’s PT3 and PT5 and women’s PT1 and PT3.

Justin Godfrey held off the challenge of Kyrgyzstan’s Nurbek Toichubaev to win the men’s PT3 in 70$41, while Jonathan Goerlach took top honours in the men’s PT5 in 74:17.

Emily Tapp clocked 75:33 to finish ahead of fellow Australian Sarah Tait in the women’s PT1, and in the women's PT3, sole competitor Kerryn Harvey managed a time of 83:58.

Great Britain’s George Peasgood won the men’s PT4 in 62:33 and there were two victories for the United States thanks to the efforts of Sara75Reinertsen, winner of the women’s PT2 in 89:44, and Elizabeth Baker, winner of the women’s PT5 in 75:10.