Home favourites Talita Antunes and Larissa Franca will be out to prove American Kerri Walsh Jennings's dream of a fourth successive Olympic gold is built on sand when beach volleyball returns to its spiritual home at the iconic Copacabana beach.
Walsh Jennings partnered Misty May-Treanor to form what is often hailed as the greatest beach volleyball team ever, capturing Olympic gold at Athens, Beijing and London.
May-Treanor has since walked into the sunset but not even the sands of time or a fifth shoulder surgery could deter Walsh Jennings, nicknamed 'Six Feet of Sunshine', from chasing her first gold with new partner April Ross.
"My shoulder injuries and surgery late last year were a bit of an obstacle but we've found an incredible rhythm," the 37-year-old mother-of-three said last month.
But there are other pebbles on the famous Copacabana beach.
The Larissa-Talita pair, who top Pool A, for instance.
The Brazilians defended their Gstaad major title by registering their fourth win in five FIVB world tour matches against the Americans earlier this month, sending an ominous signal ahead of the home Olympics.
The reigning world champion pair of Agatha Bednarczuk and Barbara Seixas also lurk in Pool B and hope to be the second Brazilian team to win the women's gold since Jackie Silva and Sandra Pires triumphed in the sport's Olympic debut at the 1996 Atlanta Games.
In the men's competition, Brazil will field a world champion team with Alison Cerutti and Bruno Schmidt in Pool A hoping to for a second gold on the beach.
The United States have dominated the Olympic sand, claiming six of the 10 gold medals, and their hopes in the men's contest will rest on the Phil Dalhausser-Nick Lucena pair.
Jake Gibb and Casey Patterson also represent the mighty Americans, who have won a gold at every Olympics since Atlanta.
