The Brazilians eventually won 1-6 6-4 24-22 - the most games ever played in a set and in a match in Olympic Doubles history.
Yesterday Jo-Wilfried Tsonga beat Milos Raonic 6-3 3-6 25-23 in the longest three-set match in Olympic history in terms of the number of games played.
Meanwhile, world number one Roger Federer went through to the quarter-finals of the men's Singles tournament after seeing off Denis Istomin of Uzbekistan.
It was a tougher than expected match for the Wimbledon champion, who made the perfect start with a break of serve in his opponent's first game but allowed Istomin to level.
The Uzbek then had three break points at 5-5 but could not take them and he paid the price, with Federer wrapping up a 7-5 6-3 victory on Court One.
Eighth seed Juan Martin Del Potro also reached the last eight, while 11th seed Nicolas Almagro from Spain beat Steve Darcis 7-5 6-3.