Local wildcard Deivid Silva has eliminated top-ranked Matt Wilkinson from the world surf league event in Brazil.
Silva won the second-round heat with a combined wave score of 14.73 to 14.50 in the fourth stop of the world tour.
"That was a tough one to swallow," said Australia's Wilkinson.
"I felt like I surfed a smart heat and I gave Silva two fours (points) that he turned into a six and an eight."
Brazilian Gabriel Medina stole the show in the one-to-two metre waves when he landed the first-ever backflip rotation in competition to score a perfect 10 in his comfortable win over compatriot Alex Ribeiro.
Australia's world No.7 Julian Wilson was eliminated by Hawaii's Dusty Payne while Aussies Josh Kerr and Adrian Buchan were also knocked out.
There was some good news for the Australians with tour rookie Jack Freestone beating Jeremy Flores 14.57 to 11.77 while Matt Banting and Stuart Kennedy moved into the third round.
Kennedy lines up against fellow Australian Davey Cathels in round three while Banting takes on Tahitian Michel Bourez and Freestone takes on South Africa's Jordy Smith.
Following the completion of the men's second round, the women's event ran only two heats of the fourth round before conditions deteriorated.
Hawaii's Malia Manuel defeated Australian tour rookie Kelly Andrew to set up a quarter-final with Sally Fitzgibbons.
"I knew with this wind coming up and the tide going out that I did not have high expectations and it would be a battle of 6 point rides," Manuel said.
"Luckily, I had a good backup score. I was trying to hunt for waves and get into that beach break rhythm."
American Sage Erikson was eliminated by Hawaii's Tatiana Weston-Webb in the last heat of the day.