Portraits of the five winners since then, Bjarne Riis, Jan Ullrich, Marco Pantani, Lance Armstrong and Floyd Landis, have long gone.

Riis, winner in 1996, recently confessed he had doped, while his young German teammate, Jan Ullrich, victorious in 1997, was sacked by his team and subsequently implicated in theOperacion Puerto blood doping affair which exploded across cycling last summer.

Pantani, winner in 1998, was disgraced after a doping scandal ten months later and then died of drug addiction, while Armstrong has been repeatedly accused of doping by the French media and by former confidantes. The Texan has vehemently denied anywrongdoing, but his name is now persona non gratawithin the race organisation while his ties with last year's winner, Floyd Landis, who subsequently tested positive for testosterone, have not boosted his standing in France.

Just as the Tour, desperate for a fresh start, rejoiced in this summer's exuberant opening weekend in London, along came Michael Rasmussen. Skeletal, shavenheaded, evasive and isolated, the Chicken (as he was dubbed) and his bizarre behaviour was a risk too far for everyone involved in this year's Tour. As the race wound through the Pyrenees and Rasmussen streaked ahead of the Tour peloton, an unexpected victory within his grasp, the doubts about him reached critical mass.

The 33-year-old Dane missed no less than four outof-competition doping controls prior to the start of this year's race. If that blotted his copy book . . . "an administrative error" he claimed . . . the jumble of excuses and justifications only made things worse.

Yes, he had received letters warning him over his conduct, yes he had held a racing licence in Mexico and Monaco . . . and had undergone no doping controls in either nation . . . and yes, he had mixed up names and dates and refused to accept the jurisdiction of his own anti-doping agency in Denmark, but, he insisted, "You can trust me."

In the end, despite the fact that he had not failed a dope test, nobody, not even his own team, trusted him anymore.

Rasmussen had become entangled in his ownweb. Two witnesses claimed to have seen him in the Italian Dolomites in June, even though he had told both his Rabobank team and the International Cycling Union (UCI) he was training in Mexico.

That was it: his sponsor finally cracked under the pressure and late last Wednesday night, the Chicken hit the road.

If Prudhomme has his way, Rasmussen will be the last of the riders who climbed through steep hairpins as if powered by rocket fuel, who showed no sign of breathlessness after six hours in the mountains, who overnight became a brilliant time triallist capable of easily distancing Olympic champions. The generation of "extraterrestrials", as the French call them, may be coming to an end.

On Friday, embittered by the scandals that have nullified the Tour and enraged by what he sees as the lack of support from the UCI, Prudhomme was on the warpath. "Next year's Tour will be as clean as possible, " he said. "That means we will work with WADA (World Anti-Doping Agency) and the French antidoping agency (LNDD). Without the UCI, it will be better.

"Let's get straight to the point, " he said. "I respect the UCI, but right now I trust nobody . . . least of all the UCI. We were ready to work with them to fight doping and have supported them financially. But when you have made an alliance and looked the other person right in the eyes, then you expect to be told the truth. But that didn't happen."

"You can't make the Tour de France responsible for everything, " said Prudhomme. "We also have an international federation, the UCI, but they are worth nothing."

In an interview on French television, UCI president Pat McQuaid insisted, "I love the Tour, " but his protestations fell on stony ground. In truth, the Irishman, who has described race organiser ASO's recent statements as "unbelievable, " has faced an almost impossible job.

During the course of his reign, Verbruggen's alleged reluctance to tackle doping or to listen to those who predicted an ethical meltdown of the kind seen on this year's Tour became legendary.

McQuaid was effectively passed a poisoned chalice when he inherited the role from Dutchman Hein Verbruggen, a former marketing manager for Mars. On Friday, Prudhomme went even further, suggesting that Verbruggen, now McQuaid's vice-president, was in fact still "pulling the strings" and stating the UCI "never wanted a clean Tour."

"Verbruggen wanted to buy the Tour, through a Dutch investment fund but we said 'No thanks', so now he wants to get the price down, " he said.But what really lies behind cycling's decade of doping? To many minds, the scandals on this year's torrid Tour have been the inevitable consequence of a lack of regulation, allied to new levels of corporate investment, fast-advancing medical technologies and an unhealthy growth in the popularity of unscrupulous and highly-paid sports doctors. Despite all of its problems, cycling is now wealthier than it has ever been and all those involved, the media included, have been happy to ride the gravy train.

Not for the first time, the French press have responded scathingly to the Tour, calling for "clean cycling, " and accusing both Prudhomme and Tour president Patrice Clerc of hypocrisy and of using ethical arguments to hide their real interest, that of protecting their globally recognized and highly lucrative brand.

"The Tour is a festival of doping, " wrote one paper. "It always has been and always will be." For the moment, despite all the hand-wringing and tub-thumping, the chaos is such that the festival of doping seems likely to continue. At yesterday's stage start in Cognac, both Prudhomme and McQuaid ignored each other and then, in separate interviews, took each other apart. It will take far more than passionate speeches from either man to change the mentality of a sport that long ago mislaid its moral compass.

A DECADE OF DOPING: 1996-2007 1996 Tour winner Bjarne Riis is feted in Denmark, but refuses to answer direct questions over doping, saying, "I have never tested positive." Riis finally confessed to doping this year.

1997 Riis' protege Jan Ullrich wins and becomes a national hero in Germany. Ullrich, who also wins the Tour of Spain and an Olympic gold medal later in his career, is withdrawn by his team and then sacked after the Operacion Puerto investigation, in July 2006, links him to blood doping practices.

1998 The Festina Affair derails the Tour, but Marco Pantani wins in Paris, only to be implicated in a doping scandal in 1999. Six years after his win, a drugravaged Pantani is found dead in a Rimini hotel room.

1999 . . . 2005 Lance Armstrong wins seven successive Tours, but is dogged by allegations of doping throughout. In August 2005, French newspaper L'Equipe claims the American had EPO in his blood during the 1999 Tour.

Armstrong denies doping.

2006 Pre-Tour favourites Ullrich and Ivan Basso are dramatically kicked off the Tour before it starts, heralding claims of a new era of propriety . . . until race winner Floyd Landis tests positive three days after celebrating victory.

2007 Another fresh start for the Tour falls flat when Patrik Sinkewitz of the apparently clean T-Mobile team fails a doping test, as does pre-race favourite Alexandre Vinokourov, and the little-known Cristian Moreni.

Race leader Rasmussen is evicted by his team after they claim he has lied to them about his whereabouts in June.