The goofy footer won his men's round two heat on Thursday with a two-wave total of 14, defeating Peruvian Lucca Mesinas (13.4), Argentina's Leandro Usuna (12.2) and Portugal's Vasco Ribeiro (11.67) in small surf.

It came a day after Callinan was the standout surfer for the Australian side in the Aloha Cup relay event.

"I guess it's different to everywhere else, normally you just debrief with the coach, but here you've got the whole team spirit thing happening and we get a little ring of fire going, and it gets the spirits high and pumps you up a lot, it's great," Callinan said after his heat win on Thursday.

"It's fun. It's taken some adjusting. There's a lot of heats, if you win or lose, but it's a really cool event, it's fun and there's a lot of good surfers here, even some unknown ones."

Australia, also featuring Owen Wright, Sally Fitzgibbons and Nikki Van Dijk, edged out South Africa 38.191 to 38.112 in a nail-biting cup final.

The United States (35.383) were in position to win but a time penalty against 11-time world champion Kelly Slater relegated them to third. Japan (28.14) were also in the decider.

Callinan's 7.33 wave score led Australia to the gold medal.

"It's a great feeling to be a part of a team," Callinan said.

"It's so different for our sport to be here representing Team Australia and to get a win is amazing.

"It had a relaxed vibe to it and all of the other countries involved looked like they were having a lot of fun. We really embraced the opportunity."

Callinan faces Filipe Toledo (Brazil), Edito Alcala Jr (Philippines) and Roberto Araki (Chile) in round three of the men's division.