Australian Jack Robinson sent world number one John John Florence home from the Olympic surfing competition, riding tough in their round-of-16 clash.
In deteriorating conditions that forced the women's heats to be abandoned on Tuesday morning (AEST), Ethan Ewing joined Robinson in advancing to set up an all-Aussie quarterfinal.
A storm system south of French Polynesia, hosting the surfing for this year's Olympics, made for terrifying surfing in Teahupo'o.
The wildness elevated the blockbuster Robinson-Florence heat between the World Surf League's (WSL) number one and three ranked surfers.
In noticeably bigger surf than previous days, neither were able to put a meaningful score on the board in the first half of their 30-minute heat.
Chasing a score, Robinson and Florence both disappeared into the wash and required rescuing from jetskis within seconds of each other.
Robinson stood tall after dicing with the reef, plunging into a barrel to score 7.17 in a decisive ride.
A second score took the Western Australian out of reach of Florence, the two-time world champion, eventually winning 13.94 against the Hawaiian's 9.07.
The result was a repeat of the 26-year-old's win from April's Margaret River Pro.
Shortly after Robinson's progression, Ewing joined him after defeating Australian-born Connor O'Leary, representing Japan.
Their heat resembled a battle to survive in the barrels, with both men taking all manner of tumbles, including one cringe-inducing face plant by O'Leary.
Wave selection was paramount and Ewing did best: scoring an 8.67 with a deep run to defeat O'Leary 14.17 to 11.00.
Earlier, Joao Chianca triumphed in one of the greatest heats in the two Olympics of the sport's history, defeating Morocco's Ramzi Boukhiam 18.10 to 17.80.
Chianca's reward is an all-Brazilian quarter-final with Gabriel Medina.
There will be three quarterfinals pitting compatriots against each other, with Tahitian Kauli Vaast, representing France, against Joan Duru.
The final quarterfinal will see Peru's Alonso Correa take on Brazil's Reo Inaba, who progressed with a score of just 6.00.
With the women's round three postponed and worsening conditions forecast for Wednesday (AEST), the surfing appears certain to be kicked into reserve days.
AAP
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