It is always a nervous time and even Juan Martin Hernandez, the glorious Argentine back who is unarguably for me the richest talent on rugby’s planet, was feeling the tension. “We know that there are no limits; after the first pink one, we knew that anything can happen.”

Last week saw the unveiling by Stade Français of a new playing kit. Last season’s was shocking pink with a fetching border of flowers. Surely opponents are merciless with their sledging? “Actually, the players are fine. However, when it all goes quiet when I am kicking for goal, the fans come up with all sorts of things,” Hernandez says.

The unveiling at the adidas store in Paris brought gasps even from devoted Stade followers, those used to the dizzy vividness surrounding their club, who draw 80,000 for big matches and who publish a calendar featuring their players naked, a publication labelled “homoerotic”. As far as I am qualified to judge, which is not very far, it does come very near the, er, knuckle.

And so to the new kit. Stade Français start their Heineken Cup campaign on Saturday in a large blue number, containing images of Blanche de Castille, a French heroine of the 13th century whose images are produced, as the publicity points out, “in the fashion of Andy Warhol”. Hernandez has a confession: “I like it.”

He fits perfectly into his shirt, into this environment. And not for a moment because he mistakes the gaudy trappings and glamour of his life with the reality of professional sport. He is not seduced by those (and I am one) who call him the Maradona of rugby. “The Maradona comparison is an insult to Diego,” he says. “He is one of the greatest Argentinians.” Inconveniently for Hernandez, however, our number includes Maradona himself.

“I was at an airport after the World Cup, and the phone rang. A voice said, ‘It’s Diego Maradona.’ Of course, I did not believe it. But he kept on claiming to be Maradona and I had to believe him. We spoke and he congratulated me on what I had done and he even mentioned a drop goal I had scored with my left foot against Ireland. He is left-footed but I didn’t tell him that my right foot is my stronger. When I put the phone down, I could not speak for two minutes. My girlfriend got anxious. ‘Who was that? What has happened?’ she asked. To speak with Maradona was absolutely incredible.”

Hernandez is delightful company, a remarkably modest and decent man. Fernan Dubie, a long-time friend, says: “He is humble and shy. He is not accustomed to fame. He is comfortable with his friends. Every time he comes home to Argentina, he finds time to be with us.”

What is not at issue is his sporting greatness. There was enough evidence in the 2007 World Cup to fill wheelbarrows. He is one of the few practitioners out of hand who can still boom the ball from goal-line almost to goal-line. He is, too, a brilliant tactician, especially when moving forward from full-back to his preferred position as fly-half, and yet he has the animal physicality of the best flankers. If the move he has called is to be abandoned, he can beast the ball up with astonishing power.

His dexterity is from another planet. In the bronze medal match between Argentina and France, in which he and his country were magnificent, Hernandez threw out a bullet spiral pass from his left hand that sliced through the Parisian evening, unleashed deeplying Argentine backs to the right by enabling them to hit the ball at top pace and made a try. It was a pass and an instant worth the price of admission.

He is impatient with the rugby world that the Pumas, scandalously, are still outside. But he is hopeful. “There are some great players coming though. We have to find the soul of the new Puma team, like we found the soul of the old team. Remember that it took us five years together.”

Hernandez was born in the San Isidro neighbourhood in Buenos Aires, an area in which high-class suburbs seem to rub shoulders with shanty towns. He was clearly marked for greatness. As Dubie recalls: “He always had that extra touch. As a kid, they would tell him to try to pass the ball to others, as otherwise he would score every time he touched it.” His sister, Maripi, is a hockey player of note, part of the Argentine team that won the World Cup in 2002 and a bronze medal at the Athens Olympics.

In his mid-teens Hernandez first realised he could play professional rugby. “It was when coaches of opposing teams came up to me at the end of games to compliment me. I don’t know what it was that they saw, but I started thinking about my passion for rugby driving a career.”

The global bush telegraph of rugby swung into action. When he first made the Argentine Sevens team there was interest from Wasps and a six-month trial was arranged, only for Hernandez to wreck his knee in a tournament, causing the visit to be abandoned. He arrived in England for a trial with Leicester but visa problems robbed both parties of what could have been a fruitful relationship. Leicester revived their interest 18 months ago, but Hernandez is still at Stade, and happy.

Would he ever cross the Channel? “The question does not arise for a year, until the end of my contract, so I have plenty of time to think about it.” You have to say that, in terms of comparative lifestyles, Paris has just a little to commend it.

There is no option for Stade. They have to win something and they are prepared to leave the louche life behind. Can you die for a concept like Stade Français or play for a jersey with an image of Blanche? “The intensity here comes from within the group. There is no club like Stade and the pressure to win is always good pressure. That is exactly why we are here, because this is a big club with big expectations.”

The Heineken Cup is his goal. “I would swap it for the French Top14. We lost in the final in 2005 at Murrayfield against Tou-louse and three months later it was still hurting. It took a long time to get over it.”

That suggests the individual cares for his team; and that the lordly and even arrogant carriage of some truly brilliant sportsmen is something Hernandez adopts only on the sports field itself. Around European rugby this season, that will be bad news for some.