The boy was about 14 years old, wearing an AC Milan football shirt. "Excuse me, sir," he said, with great politeness. "You are sitting on our goal." And so I was. I was sitting on a pink concrete bench, beside a shabby pink-concrete open space, 80 yards long but only 12 yards wide. All around were blank-faced tower blocks. Just beyond them were pretty bungalows. Beyond those were the scrub-covered hills that decorate the Provence of Marcel Pagnol and Paul Cézanne and Peter Mayle.
On this narrow strip of pink paving-stones, at the northernmost tip of the crescent-shaped city of Marseilles, generations of boys have played a cramped version of football, in which wing-play does not exist. It cannot. There is no room for the wings.
Those generations of boys have included Yazid Zidane, who left here at the age of 13 to become a professional footballer. He is now – as Zinedine Zidane – the most expensive and probably the most talented footballer in the world (a central midfielder, naturally, given the shape of the long, thin, concrete pitch on which he played from the age of five). Before he left to join the Cannes junior team in 1986, Zidane lived with his family in one of the flats in a two-storey building overlooking the concrete pitch. This is, in fact, the Place Tartane, the main square of the cité (public housing estate) of La Castellane.
After I had moved from the top of their goal, the latest generation of boys to occupy this space – aged between five and 19, from at least six different national backgrounds – pointed out the building where Zidane had lived, a few yards away. The flat was so small that he and his parents, three brothers and one sister, had to sit down to eat in shifts.
"He's a big star now. He's a millionaire. We used to see him back here all the time, but since he moved to Real Madrid [from Juventus last year, for a record transfer fee] we don't see him at all," said Agueni, 13, from the same Kabyle ethnic minority in Algeria as Zidane himself.
"He's busy. We understand that. And he still gives us the money to run our football team," said Alex, 14 (a handsome boy of African origin, already built like a footballer and with a burning ambition to be one).
"He belongs to the whole world now but he's still from here," said Akim, 14 and 6ft tall, whose parents came from Cameroun. "He's a son of La Castellane. He used to play on these stones. You can't help dreaming when you think of that..."
La Castellane is one of the toughest neighbourhoods in Marseilles, which is probably the toughest city in France. Before I came up here, people in the city-centre of Marseilles advised me to reconsider my plans; or to be very careful.
In the first round of the French Presidential election last month, La Castellane voted 30 per cent for the Front National leader, Jean-Marie Le Pen. In effect, he won almost all the votes of the ethnically European people living here. "They vote that way because they are sick of the violence and insecurity and because the North Africans are aggressive and Muslim and don't want to mix," said Alain, a man I met beside a giant advertising portrait of Zinedine Zidane that stares moodily out from the coastal road at the opposite end of the city. "La Castellane is a very violent place. They don't like outsiders. They destroy everything up there," he said.
Four years ago next month, France won the World Cup with players from every indigenous and immigrant minority in France. A young man with Mr Spockish good-looks became the poster-child for a widely cherished hope that the triumph of "Les Bleus" would help to heal the country's racial divisions. It was hoped that the team – and especially Zidane – would give young French people of North African origin (known as beurs) a sense of French identity for the first time. Just as importantly, it was hoped that he would project a positive image of North Africans to mainstream France for the first time.
Four years later, with substantially the same France team about to defend its title in the Far East, those hopes might appear to have been foolish. The racist, anti-immigrant Front National reached a new high watermark in the first round of the presidential election last month. Violent crime, especially in poor, immigrant areas like La Castellane, is rising. Young French men of Algerian origin booed and jeered the French national anthem before a France-Algeria football match – with Zidane on the pitch in French blue – in Paris last year. So what happened to the "Zidane effect"?
In La Castellane, built in the 1950s, there are 6,600 people from at least 15 different ethnic backgrounds: beurs, Africans, Turks, gypsies, Albanians, Iraqis, Kurds. There is 60 per cent unemployment. Four years later, what do the kids here think of football and France and Zidane?
Kalef Bouamama, 19, plays midfield (Zidane's position) in one of the dozen teams run by the local football club – Association des Jeunes de la Nouvelle Vague – which is almost entirely sponsored by Zinedine Zidane. He said: "I was born in France. I have a right to be considered French and I have a right to be respected as French but, in my heart, I am Algerian. Why? Because it is my country. That is all."
Djamel Tachoujakt, 15, also of Algerian origin but born in France, was one of the kids playing on the pink concrete slabs, before he took a break and sat down to speak to me. He said: "In Marseilles, no one supported the France team before 1998. We supported OM (Olympique Marseille). We didn't care anything about the France team. Zidane changed that. Now we support OM and Zidane and through Zidane, we support France."
Seief Kahdri, 14, whose parents came to Marseilles from Tunisia, said that all the young people of La Castellane would be gathering in the "Snacky" café for the awkward, early-morning kick-offs of the France games in Japan and South Korea over the next few weeks. "When France score, you will hear our cheer all over Marseilles," he said.
None of the boys showed much interest in French politics, although one, Majid, 14, suggested that the big vote for the Front National was "a bad joke". "They tolerate us when we can play football well but, otherwise, there is no room for beurs or for people from places like this. As soon as they see the address, La Castellane, they don't want to know you."
Despite the terrible warnings I was given in Marseilles, I never once felt threatened in La Castellane.
Rachid Zekraoui, 30, who works in the estate's community centre, said: "People look at Zidane's talent and they accept that it was bred in a place like this. But they are also impressed by his charm, his intelligence, his eloquence, his politeness. They forget that that was also bred into him here.
"There are kids in La Castellane who have gone off the track, and families struggling on the minimum wage, or on the dole, who have given up. But there are also many families, just like Zidane's family, who try to bring up their kids the right way. You will find lots of kids here who are polite and friendly, just like Zinedine Zidane."
And so it proved.
All the talk of their estate as a violent place was "stupid", the boys said. It was the result of "ignorance" and "jealousy" because they had produced Zidane and the other parts of the city had not.
"There used to be violence here but things are calm now," said Nadir Mouassaoui, 14. He said that the community centre, in the heart of La Castellane, which provided activities for young people, and the Zidane-sponsored football club, had made a big difference. So, really no violence? No crime? An older boy rode rapidly through the football game on a brand new motorbike. "He's more interested in motorbikes than football," they said and giggled. But motorbikes are expensive, I said. The boys grinned at each other. "He's in business. He's got a business," they said. "He's in the security business." They laughed again.
Two other young men in their twenties – beurs with blond-dyed hair – came up to investigate our group. I told them, also, that people had warned me of the dangers of La Castellane. I had been told that everyone would be threatening and méchant.
"We are nasty with the people we know that we have to be nasty with. You look harmless," one of the twentysomethings said. They rode off. I was not sure if that was a compliment or an insult.
Of Zidane, the kids spoke of their "pride" that he was a son of their cité, even if they rarely saw him these days. "Not everyone has talent like Zidane. Not everyone can become a professional footballer. But what he did – to leave here as a kid – took guts and hard work," said Alex Simba, 14. "That's what they tell us at the football club. That we can't all be professional footballers but we can learn from Zidane's courage, that he came from a place like this and made it in the world outside."
As Rachid Zekraoui, in the community centre, pointed out, Zidane's great talent and success cuts two ways. It shows that the son of a North African immigrant can succeed in France. But it also suggests that, even in the 21st century, a young person is "condemned to excellence" to escape from a place like La Castellane.
Even so, the Zidane effect should not be mocked. It may just be slower-acting than some people had hoped. The importance of Zidane is that he offers young French people – brown, white and black – a different way of forming their prejudices. The attitudes of older French people, and older children of immigrants, were formed years ago. Even Zidane's talent and charm will not change them overnight. Meanwhile, he offers young white French children as they grow up a successful and gentle image of North Africans. He offers the children of immigrants a positive self-image, which is not rooted in drugs or violence.
The question remains: what do they do with that more positive self-image? What does Alex Simba want to achieve in life? "I want to be a footballer. Do you think I have the talent? Do you think I could make it in England?" The boys cluster round saying their dream is to be détecté (spotted) by a talent scout. Did I think that English clubs would be interested in them? Their club was organising a trip to Paris, they said. Would any junior teams in Britain be interested in inviting them to come over and play?
In truth, all the kids I met were already too old for a career in professional football, and must, in their hearts, know that. Only one, Kalef, aged 19, spoke of any other ambition. He said that it was his hope that, some day, he would "get a job".
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