In choppy four foot waves America's Bobby Martinez caused the upset of the event when he defeated the King of surfing Kelly Slater.

Currently sitting 55th in the Tour ratings, Martinez produced some impressive moves to win the close hard fought heat 14.50 to 14.10.

After the final hooter Slater chose to remain out in the water, free surfing down the beach for 2hrs, perhaps trying to avoid untimely attention from the media and massive crowd.

“There were some lefts and Kelly (Slater) went down to the rights and you’re always worried that he sees something that you don’t,” Martinez said. “I just got lucky, things worked to my advantage. I got that one right under his priority and that’s what he usually does. I thought I’d try and reverse the role. ”

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Former two time world champion Mick Fanning was knocked out by crowd favourite Raoni Monteiro. The Brazilian scored an 8.67 on the back of two critical and committed backhand turns, leaving Fanning to play catch up as the heat time ticked away.

Joel Parkinson continued his impressive form, taking his round 3 heat and followed up with the highest single-wave score of the entire event, a 9.73 out of 10 to win his three-man round 4 heat in the last seconds, advancing directly into the quarterfinals.“It’s kind of one of those things where you’re only as good as your last heat and once you have a shocker you don’t want to have another one,” Parkinson said. “It might have been a blessing in disguise (to lose in Round 1). I’m glad I got that one out of the way and my strategy is good and I feel good.”Parkinson’s guaranteed 5th place result at the Billabong Rio Pro temporarily moves him to the No. 1 position on the ASP World Title Rankings after Slater’s early elimination.Steph Gilmore knocked out of world title race The day’s second-highest heat-total went to compatriot Taj Burrow who scored an 18.40 out of 20 to advance to the quarters.“That felt good, I felt good out there for sure,” Burrow said. “As long as I can get a wave with an open face I feel like I can get the job done, but that’s the hard thing. Sometimes you just get on a roll and it has a lot to do with confidence. For me confidence is a big thing and it’s a tough one for me. When it’s high, I don’t know what it is, it just does it. I feel like I’ve been on tour long enough to win heats.”Taj Burrow: He can surf, but can he run?