Needing a major score with 10 seconds remaining in the heat, Dos Santos threaded a lengthy forehand barrel to attain a 9.87 out of a possible 10 and the emotional win.
“That wave came to me at the very end and I was just hoping for a chance to show what I can do,” Dos Santos said.
“That wave was so good and it just allowed me to pull in early and keep running through it. That was my last chance – it was either make it or go home.
"I knew I had to get the best waves and get as deep as I can. I knew Kelly (Slater) was going to post high scores so I just had to do my best. I’m really happy right now, but there’s a long way to go so I need to focus.”
While Slater bowed out of the Billabong Pro Tahiti uncharacteristically early, the iconic Floridian remained ever-gracious in defeat and will return to competition at the upcoming event in California.
“I honestly don’t know a whole lot about Ricardo,” Slater said. “I know that he won the Trials last year in huge surf and won the Trials this year in small surf so he’s obviously very competent out here in any kind of conditions.
"I’m disappointed to lose early, but more so because tomorrow could be really good. I think that tomorrow could be really classic conditions at Teahupo’o and hopefully I’m able to get waves somewhere.”
Dos Santos's fellow Brazilian Gabriel Medina collected a perfect 10 in the final heat of the day, with an incredible forehand drop into a bowling barrel at Teahupo’o.
"“I’ve gotten a few 10s before but nothing like that wave,” Medina said.
“It’s an honour to be here competing at Teahupo’o and I have a lot of respect for John John (Florence) and Kieren (Perrow). They are both great tube-riders so I knew I had to do my best. Very thankful to get through and looking forward to tomorrow’s finish.”
Results and matchups:
BILLABONG PRO TAHITI ROUND 3 RESULTS:
Heat 1: Mick Fanning (AUS) 14.17 def. Fredrick Patacchia (HAW) 8.34
Heat 2: Julian Wilson (AUS) 13.83 def. Adrian Buchan (AUS) 9.37
Heat 3: Taj Burrow (AUS) 14.04 def. Kai Otton (AUS) 11.00
Heat 4: Owen Wright (AUS) 18.30 def. Miguel Pupo (BRA) 17.50
Heat 5: C.J. Hobgood (USA) 18.30 def. Michel Bourez (PYF) 15.17
Heat 6: Ricardo dos Santos (BRA) 18.34 def. Kelly Slater (USA) 16.44
Heat 7: Joel Parkinson (AUS) 12.83 def. Taylor Knox (USA) 4.47
Heat 8: Jeremy Flores (FRA) 15.60 def. Heitor Alves (BRA) 12.60
Heat 9: Damien Hobgood (USA) 15.10 def. Josh Kerr (AUS) 11.93
Heat 10: John John Florence (HAW) 13.30 def. Brett Simpson (USA) 13.17
Heat 11: Gabriel Medina (BRA) 13.60 def. Alejo Muniz (BRA) 4.73
Heat 12: Kieren Perrow (AUS) 16.87 def. Adriano de Souza (BRA) 10.67
BILLABONG PRO TAHITI ROUND 4 RESULTS:
Heat 1: Mick Fanning (AUS) 15.60, Taj Burrow (AUS) 9.10, Julian Wilson (AUS) 2.80
Heat 2: C.J. Hobgood (USA) 16.76, Owen Wright (AUS) 15.60, Ricardo dos Santos (BRA) 9.67
Heat 3: Joel Parkinson (AUS) 18.23, Jeremy Flores (FRA) 17.77, Damien Hobgood (USA) 14.47
Heat 4: Gabriel Medina (BRA) 17.83, John John Florence (HAW) 7.00, Kieren Perrow (AUS) 3.23
BILLABONG PRO TAHITI ROUND 5 MATCH-UPS:
Heat 1: Ricardo dos Santos (BRA) vs. Taj Burrow (AUS)
Heat 2: Owen Wright (AUS) vs. Julian Wilson (AUS)
Heat 3: Jeremy Flores (FRA) vs. Kieren Perrow (AUS)
Heat 4: John John Florence (HAW) vs. Damien Hobgood (USA)