There's always a sense of melancholy when a road trip ends, especially one that started with great expectations. Alberto Contador was beaming as he received his golden fleece on the Champs Elysees yesterday - but the fabled maillot jaune is now, more than ever, viewed in a shroud of suspicion.

This should be a feel-good story but it doesn't feel very good writing it. Cycling's reputation, fragile at best, has been further fractured, almost fatally, by the events of the past seven days.

In the twelve months before the next race leaves Brittany, there is much hard work to be done. There are political games at work that make FIFA look like a friendly parish council but behind the bickering there is an acknowledgement that the race, and maybe the sport, will not survive unless drastic action is taken.

All of which will come as little consolation to Spaniard Contador, who should be waking this morning to headlines praising his performance in a race that will forever be tainted by tawdry tales of dodgy doctors and shady soigneurs.

The youngest winner of the race since Jan Ullrich in 1997, his winning margin over Australia's Cadel Evans - just 23 seconds - is the closest since Greg Lemond beat Laurent Fignon by eight seconds in 1989.

He should be reading about his remarkable recovery from the blood clot and stroke which left him fighting for his life, and in a coma for ten days, after a crash in the 2004 Vuelta a Asturias. But instead the pages will be filled with post mortems and grim prognoses for the future of cycling's showpiece.

Tour de France organisers the Amaury Sport Organisation are now engaged in open warfare with the sport's world governing body, while sponsors and television companies have an uneasy eye on the bottom line.

Contador himself again went on the defensive last night, amid continued allegations of his involvement in the Operacion Puerto drugs probe that claimed the career of Ullrich and others.

Seven-times winner Lance Armstrong - who knows a thing or two about both life-threatening health scares and allegations of foul play - was in the Discovery team car to watch Contador anointed as his successor.

"I think we've seen the future of Spanish cycling, perhaps international cycling," he said.

At just 24, Contador - who few believed could win the race when it rolled out of London - has his best years ahead.

"Since Lance retired people are always asking, Who is the next Armstrong?'" said Johann Bruyneel, Discovery's director and Armstrong's long-time confidante.

"I think he's up there on the podium, in the yellow jersey. They are obviously different types of riders but Alberto has many key characteristics that remind me of Lance. He is a rider capable of executing a strategy, a plan for a race. He has the world at his feet now."

Scotland's David Millar failed in his promise to add to a collection of three stage wins, despite involvement in three prominent breakaways. He finished yesterday's final stage in eighth and completed the race just over two-and-a-half hours behind Contador.

Millar will leave Saunier Duval at the end of this season and will announce this week that he will join Wall Street-backed and Spanish-based outfit Slipstream.

Slipstream does not currently have a place on the UCI Pro Tour but sporting director Jonathan Vaughters has been busy recruiting some top talent in the last three weeks.

Millar will join close friend David Zabriskie in the squad, which is believed will adopt an aggressive anti-doping policy.

Vaughters, a former US Postal team-mate of Lance Armstrong, has signed a deal with the Agency for Sporting Ethics, which will see his 23-strong riders' roster undergo 1,200 drugs tests during the course of next season - 20 times more than they are tested by the UCI, cycling's beleaguered world governing body.

"David has had a rough time in the past but he buys into the concept of our team and we're delighted he is on board," said Vaughters.

"We want to lead the fight against doping. When the public sees one of our riders win, they will know for certain that they are clean. If they dope, they won't compete, they won't have a job with us.

"David is a very intelligent man and a real creative thinker. He's brought enthusiasm to the team and some great ideas.

"He knows that regaining the public's trust and re-establishing cycling's credibility is so important for cycling's future.

"But we are also looking forward to helping David develop as a cyclist - he's got some good years ahead."

Vaughters talks a good game about renewing confidence in the sport and he has a useful ally in reformed doper Millar.

Cycling might look like the dirtiest sport in the world but with the zeal and passion of men like Vaughters, it could yet end up the cleanest. And when being positive can be so negative, that's the most upbeat note on which to end this downbeat Tour.