Brazil's passion for 'futebol' famously knows no bounds -- and comes in all shapes and sizes in this giant country, with Rio's beach culture the perfect backdrop.
Love of the Beautiful Game extends well beyond classic 11-a-side and, from before sunrise to long after sunset, dozens of balls whizz through the air as players do battle right to the water's edge.
Recent years have seen a whole host of formats take root and flourish in Rio wherever players can mark out even a small space in a city much of whose topography, beach aside, is a mix of mountains and urban concrete jungle.
Rio residents or "cariocas" adore beach football, footvolley -- beach football's spectacular cousin -- and futsal, the mini indoor pursuit at which Brazil excels.
Thousands of Brazilians can't get enough of futsal -- which is where Barcelona star Neymar was initially discovered.
Brazilians who live for both soccer and the beach were delighted when January brought a Copa America beach football triumph featuring a 10-1 thrashing of old rivals Argentina.
Futsal and beach soccer today are booming as both enjoy increasing TV coverage.
Footvolley is also prospering, providing a livelihood for top-drawer players.
Marcus Vieira, winner of the International Footvolley (the Brazilians say Futevolei) Cup in Germany last year, says TV exposure is fueling rising prizemoney.
"Footvolley makes for great TV -- just after the (massively popular) soap operas," he told AFP before training on Rio's iconic Ipanema Beach.
The game traces its origins back to the mid-1960s, where former Botafogo star OctÃ¡vio de Moraes began playing on Copacabana Beach, next door to Ipanema.
"In those days the police wouldn't let people play soccer on the beach but people got round it by playing on a beach volleyball court. They said, 'let's kick the ball over the net' and so futevolei was born," says Vieira.
Some famous names played their part -- Maradona starred in one Copacabana session, while 1994 World Cup winner Romario is another devotee.
As Vieira, who coaches eight hours a day, says: "What more recommendation do you need?"
Foot-volley and beach football stars won't strike it as rich as Neymar and co, but neither will they turn up their noses at first prizes touching $20,000 at some events.
"Top players can make a living doing this. It's not like you need much equipment -- you don't even need a beach; just sand," grins Vieira.
Players include 29-year-old architect Tiago, who comes to Ipanema every evening after work, and 19-year-old 'Juninho', who dreams of being a professional 11-a-side footballer.
"Ronaldinho -- now he's my type of player. And he's great at futevolei too," says the softly-spoken teen.
Women are joining in, with 22-year-old Anna Borela a star pupil of Vieira.
"I live near the beach so gravitated towards it. I love the close control skill. I play all the time -- I think I was born for it," Borela told AFP.
"My favorite move is the shark," she adds of the move which involves leaping at the ball at head height and flipping the ball over the net with one's feet.
Such is the advance of myriad formats that other sports are looking over their shoulders, including beach volleyball, which already has Olympic status and where Brazil play second fiddle only to the United States.
"I don't think they'll drive us out of town. But every sport with a football element is bound to get popular -- particularly now they're getting on TV," beach volley professional Moises Santos Merzes told AFP.
Away from the beach, in nearby Botafogo district, Franco-Brazilian Sidney Bovy organizes So-5, a five-a-side format designed for urban professionals but also for youngsters from age five.
The concept, comprising mini-leagues and 50-minute matches, is sponsored by Paris Saint Germain.
"Our idea is to create good work teams outside of the workplace," says Bovy.
"Here, we just want to play soccer. It's not about getting on TV," Bovy adds -- though you can get your game videoed.
Even nightfall can't stop true devotees.
"Our parents know where we are -- they won't ground us," says gap-toothed Tiago, 16, as he and friend Nelson enjoy a midnight beachside session of "pelada" -- a kickabout.
As more friends appear, they switch over to "altinho", knocking the ball around in a circle without it touching the ground. Others practise 'baixinhas' -- individual keepy-uppy.
Come sunrise, the night owls head home, the early birds arrive and the cycle starts all over again.