Farewell, then, to the man in silly knickers. As I watched Rafael Nadal, the French Open champion, vanish from Wimbledon in a blizzard of mistimed shots, I was reminded of the time I rode a camel. I am used to riding horses. It was not that I couldn’t ride the camel, it was just that it felt so peculiar.

I wanted the camel to like me, but I didn’t feel in a position to trust it. The response time was different, every movement felt different, the mind of the animal felt different. I did okay, but it didn’t feel right. And I suppose Nadal did okay, but it didn’t feel right for him either.

The stuff he was playing on was green and not red, it was fast and not slow, it was living and not dead. Nadal clearly wanted to make friends with it, but he never felt in a position to trust it. And so he lost to Gilles Muller, going down 6-4, 4-6, 6-3, 6-4.

Muller is not a bad player, but hardly a man from the station of the stars. On a clay court, Nadal would have had him for brekker, with a side order of muffins. In fact, he has already done so. In Barcelona in April, Muller took two games off him in two sets. But on Thursday Nadal couldn’t find his touch, couldn’t find his timing, couldn’t find his A game.

It looked like a nightmare, the kind when you run away from a fearful fiend with your feet mired in treacle. Nadal tried all he could to fight off despair, but the ball simply wouldn’t do what he told it to. How do you adjust to that? It was as chastening as it gets for a 19-year-old Grand-Slam champion.

Nadal is supposed to be the next big thing. He has been dressed to kill for this tournament: white jim-jam trousers, white muscles-vest, white bandanna ? the biggest notice-me outfit worn by a male at Wimbledon since Andre Agassi, another marketing man’s dream, turned up in a three-layer white outfit that made him look like a wedding cake.

Nadal began this tournament with a sprightly win in the first round and seemed to be hitting the ball pretty well. But on Thursday it just didn’t happen. It was hard to believe that he has ever won a match, let alone one of the biggest tournaments in tennis.

In fact, it might have been a lot worse, because Muller is not over-gifted in the killer-instinct department and was unable to bully Nadal. But he harried him into errors of shot and shot selection. Muller could see that if he kept up the pressure, he would win; and to his great credit, he was able to do exactly that.

Nadal fought back in the second set with a lot of theatrics. He has developed a very fine air-punch, his fist finishing just short of his eye, biceps fantastically flexed. At extreme moments of emotion he brings in a knee, lifted as high as his popping pecs, and it seemed for a moment that sheer physical exuberance would be enough to see him through, like the teenaged Boris Becker before him.

But Nadal could not be himself on that treacherous green stuff. Three times he took lunging, rolling falls; three more than Muller.

Each surface feels different beneath your feet, every movement you make contrasts subtly with the way it does on other surfaces. It’s bad enough if you go into a match with the best possible attitude, but if you let it get into your mind that the stuff beneath your feet is somehow wrong then you have lost before you start.

It was a fall waiting to happen. The grass traditionally lurks in wait to humble the French champion ? you have to be Bjorn Borg or Rod Laver to win them both in the same year ? and for all his excellence, for all his genuine promise, Nadal is not in that class.

There is also the fact that Nadal has had much made of him by media and marketing men. He has been praised for his sexiness, paid for his sexiness. No one did that to me when I was 19, so I can’t say what it feels like, but I would guess he feels just a little bit like God Almighty. And sport operates with extraordinary efficacy when it comes to destroying any idea you might have about your own divinity. Sport shows every sportsman his feet of clay.