Flamengo’s headquarters are located in the shady district of Gavea in southern Rio. Every day from 9am to 5pm, guided tours visit the facilities. The colours on the walls have begun to come off and weeds have spread so far over the paths that you can’t see where you are walking. The rubble of a demolished building lies where it fell. It was thought that the club would build a gym there, but somehow the money disappeared.

Most visitors are domestic tourists from one of the country’s 27 states. Flamengo is the only club in Brazil with supporters all over the country. It does not matter where Flamengo are playing, it always feels as if they are playing at home. It is claimed that they have 25.6 million supporters in the country, almost twice as many as the other Rio clubs put together. The fans call their club Maçao Rubro-Negro: “The red and black nation.”

A famous expression is painted on the wall that surrounds one of the pitches inside Gavea: Craque, o Flamengo faze m casa – “Flamengo raises the real players.” This cocky phrase was coined in 1981 when a Zico-inspired Flamengo won the Intercontinental Cup with seven of the starting 11 homegrown. Twenty-five years on, Flamengo wants to return to those days. That is why the club has established one of the continent’s largest player factories.

The key man is Tito Araujo, the 52-year-old chief of the club’s recruitment office. He decides which boys will be part of one of the five classes in the education programme: Pre-Mirim (under-11), Mirim (under-13), Infantil (under-15), Juvenil (under-17) and Juniores (under-20). Araujo works from an office behind the training ground’s enormous concrete stand, sitting straight-backed at a desk that has seen better days. Two years ago, he returned from Qatar, where he had been a physio for five years. Tacky pennants and team photos are stuck to the wall. In between them, patches of mould have created their own continents. The air conditioning rumbles noisily.

In front of Araujo are two mobile phones. One of them vibrates.

“Futebol,” he answers, and leans back on his chair. His questions come automatically.

“Has he played for a club before? Which club? What position? All right, take him to a clinic, do an ECG and a regular medical. Send the papers to me by FedEx. You know the address. Write my name on the top and the papers will be sent to me directly.”

For the last couple of weeks, says Araujo, the phones have barely stopped ringing. “Most of the time it is the mothers,” he admits. “They say their son is the best in their neighbourhood. What do we know? Flamengo cannot afford to miss out so we invite him for a trial. Behind a simple call like this, there might be a gold nugget.”

He pulls out his top drawer and throws some membership cards on the desk. The first shows a skinny eight-year-old: Adriano Leite Ribeiro, member number 24,047.

“Look at this! His mother called. We signed him straight after the first trial. He got money for the bus and free healthcare. Check out the autograph. Cute, isn’t it?”

Every year, Araujo scours the country for new talent. In Rio alone, Flamengo have 23 football academies, with another 27 across Brazil. Then there’s Araujo’s team of olheiros [eyes] who visit every pitch in the city’s narrow suburbs. The club has daily contact with feeder clubs who frequently send their best players. Those who believe that playful football on the beaches explains why Brazil has exported 3087 professional players in the last four years might like to reconsider. In fact, it is the result of hard work and a military discipline that cannot be found anywhere else in the world.

“I get upset at those who believe that players grow on trees here,” says Araujo. “We have advantages, like a climate that makes it possible to play all year around and a history that appeals to younger boys. But really, it is our consistent work with the children that makes it possible.”

He leans over his desk. “Take any player in the national team. Everyone has started in a football academy. As eight-year-olds. They are professional even before they become teenagers.”

The other mobile phone on the desk vibrates. “Futebol,” he answers, straightening his back. He listens carefully and takes some notes. One of his olheiros has spotted a nine-year-old in the province of Espirito Santo, an eight-hour bus journey from Rio. “When he calls, things are looking good,” he smiles. “We’ve had many good boys from there.”

He walks towards a wall covered in pictures of the players in the Pre-Mirim. “If I only can get two or three players to go all the way to the first team or to Europe,” he sighs, “it will pay for all our work.”

The route to professional football in Brazil begins with futsal, a Brazilian/Uruguayan invention that spread across the continent during the 1930s and which is mainly played indoors on basketball courts, with four players and a goalkeeper in each team. In Brazil the youngest futsal category is chupetinha, “the dummy”, for those precocious boys under seven.

River FC is one of Rio’s most successful futsal clubs, the place where Zico, Flamengo’s greatest ever player, began. Today, the club’s 39-year-old youth trainer Racinha is directing his seven-year-olds.

It is 9am. The boys are flying across the shiny wooden floor, attacking the goal constantly. This is not for fun; they are following a method. They already know the basic strategy of football – they even kiss their badges when they score. “It’s never too early to begin,” laughs Racinha.

The indoor hall is a two-level concrete building from the 1960s that must have impressed people back then. Lamps in the ceiling cast a sterile light over the mothers and fathers who lean over the barriers, cheering for their kids.

River FC was founded in 1914 by a group of students who thought that Rio sounded cooler in English. For several decades the club played in Rio’s Carioca Championship, but now River only play futsal. It became too expensive to maintain a grass pitch. Boys begin here at six or seven years old, and it’s not until they have been taught all the technical aspects of the game that they are released onto the grass.

“I can’t understand what you’re doing in Europe,” says Racinha, shaking his head. “You’re developing marathon runners. Your enormous pitches are breaking down the boys – there is no joy. Football should begin with a lot of ball contact and technique, in small areas. Look at Zico or Ronaldinho. Amazing players! Ronaldo, Robinho, Adriano: they all began with futsal. The entire ‘Magic Quartet’ was formed here.”

He points towards the seven-year-olds hurtling around the 25m by 18m floor. “Look at the pace! This is the secret of Brazilian football’s wonder.”

When the dummy class has finished, it’s time for the fraldinha [diapers]. “Look at Lenny,” Racinha says. “The guy with the long hair. Fluminense have already offered him a contract. Don’t you think he’s special?”

Football comes easily to Lenny. He finds the best passes and controls the ball impressively. But whether he is a future pro… well, that’s another thing entirely.

River has 30 players in every group and a third of them will be approached by one of Rio’s three big clubs before they have turned 10. Earlier this year, Vasco da Gama and Flamengo had a dispute over an eight-year-old called Fabinho from Pavuna, a miserable suburb up north. Vasco offered the kid’s father 500 reais [$300] per month – more than a federal minimum wage and easily enough to rent a three-room apartment in the suburb. Flamengo, who already had him in their academy, offered free education, health care and dental care if he stayed. Fabinho’s unemployed father thought for a while and made a decision. A lifelong Flamenguista, he declined the cash.

This situation should not exist. One of few things Pelé achieved as Sport Minister in the late-’90s was a piece of legislation prohibiting so-called “slavery” within Brazilian football. Previously, clubs did not have to pay anything to their younger players and owned the player’s registration as soon as he signed for the club. But in March 1998, “Pelé’s law” stated that all players should be free until they turned 16. The problem is that smaller clubs who develop a player from the age of eight risk losing out financially if the player changes club as a junior. And instead of being tied to their clubs, players are now firmly tied to their agents.

Two sexagenarians, Olivia and Ney, watch from the side. They run a photo agency, and are working for Rio’s futsal association.

“Do the clubs pay the boys? Damn right they do,” snorts Olivia. “Not serious clubs like Flamengo and Fluminense, but agents and other clubs pay. They write contracts with parents and tie boys to their clubs.”

Isn’t that forbidden? Olivia leans forward. “Look,” she shrugs, “this is Brazil. Here anything is possible. There are agents and clubs that pay 1000 reais [$600] per month. That’s a lot of money for a 10-year-old, more than a nurse makes. This hunt for talent has become absolutely crazy. The agents are fighting each other. If they can strike a deal and export one of their players, they’ll make 100 times more than their expenses accounts.

“I’m upset with the parents,” she says. “What happens if the boy stops developing? If he doesn’t make it through the next peneira? What will the parents then do then? They are depending on their son’s wages. That’s a burden that no young boy should have.”