Barbara Seixas and Fernanda Alves, the top-seeded team, won Pool A with a pair of victories over European duos in the specially-built arena at Meia Praia in the coastal city.

They firstly posted a 21-15, 22-20 win over Swiss qualifiers Elena Steinemann and Nicole Eiholzer.

In their second match of the day, the Brazilians, who have won both the Fort Lauderdale Major and the Huntington Beach Open this year, defeated Russia’s Svetlana Kholominia and Nadezda Makroguzova 17-21, 21-16, 15-10.

"The fans have been amazing today," Alves said.

"It’s always special to play in Brazil in the World Tour and we fed from their energy to come from behind and beat this very young and talented Russian team, which we hadn’t played before.

"Our staff briefed us well and we could prepare properly for the match."

The other two Brazilian teams to finish the first day with perfect records and a spot in the round of 16 were Carol Solberg and Maria Elisa Antonelli, who topped Pool E, and Agatha Bednarczuk and Duda Lisboa, the winners of Pool G.

Teams from four other countries also advanced undefeated, including Germany’s Julia Sude and Chantal Laboureur, Czech Republic’s Krystina Kolocova and Marketa Slukova, and Switzerland’s Joana Heidrich and Anouk Vergé-Dépré.

The Canadian duos of Sarah Pavan and Melissa Humana-Paredes and Heather Bansley and Brandie Wilkerson complete the list.

In the men’s tournament, European teams took up five of the eight automatic berths to the round of 16.

One of them went to Czech Republic’s Ondrej Perusic and David Schweiner.

The 13th-seeded team registered a surprising 17-21, 21-13, 15-12 win over Latvia's Aleksandrs Samoilovs and Janis Smedins to lead Pool D.

The other European teams advancing were Poland’s Bartosz Losiak and Piotr Kantor, The Netherlands’ Alexander Brouwer and Robert Meeuwsen and Christiaan Varenhorst and Jasper Bouter, and Norway's Anders Mol and Christian Sorum.

The non-European tandems automatically qualifying for the round of 16 were Brazil's Evandro Goncalves and Andre Loyola and Guto Carvalhaes and Vitor Felipe, and Canada's Sam Pedlow and Sam Schachter.

Pool play is due to be completed tomorrow morning with the matches involving the teams that lost their first games in Itapema.

The schedule will proceed during the day with the elimination stage and the round of 16.

The quarter-finals and semi-finals are set to take place on Saturday (May 19), while the gold and bronze medal matches will be held on Sunday (May 20).

The Itapema Open is the fourth four-star event of the 2017-2018 FIVB Beach World Tour season.