By proving himself to be the fastest man in the race, the 23-year-old from the Isle of Man is accumulating nicknames at the same rate as he is winning stages.

The "Manx Flyer" is an old one, "Cannonball Cav" is the latest, and he appears similarly unstoppable. As if to underline his dominance, and that of his Columbia team, he had ample time to sit up before the line, take both hands off the bars and enjoy the moment, while behind him, his official lead-out man, Gerald Ciolek, managed somehow to beat all the other sprinters to finish second. "That," said Cavendish afterwards, "was beautiful."

"I came to win stages in the first week," continued Cavendish, for whom today's first Pyrenean stage will provide a completely different kind of test – and one he won't relish. "But I've no intention of stopping – I intend to take it one day at a time and see if that gets me to Paris."

Yesterday's 172km stage from Figeac to Toulouse was run in awful weather, with dark clouds emitting a constant drizzle, and making the roads treacherous. On the final corner, after Cavendish's Columbia team had seemed to execute their race plan to perfection – with five team-mates controlling the peloton and leading their young sprinter to around 200 metres from the line – it seemed to go awry.

As the peloton gingerly negotiated the bend, Cavendish lost several places, in the process losing the back wheel of the faithful Ciolek. "It was a ninety-degree corner and it was really wet," explained Cavendish, "but I didn't panic when I lost my lead-out man. I know I can use my speed and go from ten back if I have to. But Gerald picked me up again and catapulted me forward. With that kind of team support all I could do was win."

Asked if he minded the foul weather, Cavendish shrugged: "I used to work in a bank when I was younger and to me it doesn't matter if it's raining, or the sun is shining, or whatever – as long as I'm riding a bike I know I'm the luckiest guy in the world."

Cavendish's victory would have been as enthusiastically welcomed by the Tour organisers as it no doubt was in the Isle of Man. With Cavendish being a vocal proponent of clean sport, and riding for a team that champions clean sport, he was the perfect winner on a day when the spectre of doping had once more reared its head, after the previous evening's news of a positive test by the 37-year-old Spaniard Manuel Beltran.

Half an hour before the start of yesterday's stage, the other British rider in the race, David Millar, emerged from his Garmin team bus and walked straight into a throng of reporters. Millar, who has taken on the role of spokesman on all matters related to doping after serving his own ban for EPO use in 2004, knew to expect that, and he had clearly thought about what to say, if not exactly how he would say it.

"Yes, I am a little surprised they're still in the race," he said of Beltran's Italian team, Liquigas.

"If (Beltran] is an anomaly within their team, and they're convinced the other guys in the team are doing it the right way, then they have a right to stay in the race. It's up to them now to convince everyone that they are doing it the right way."

It was as he responded to the next question that Millar's voice and manner betrayed his rage, directed this time not so much at Beltran, but at the storm his positive test had whipped up. Asked if he was surprised that in 2008 a rider had used EPO, Millar responded: "It makes me f***ing pissed off when people are surprised that this happens.

"We've been decades to get to this point, and if anybody's naïve and foolish enough to think that we're never going to have a positive control again then you may as well go home and not cover this race.

"The media has a responsibility to understand that this is no way going to be the last positive test we're going to have; it's going to go on for years. That's professional sport – as long as there are doping controls, there will be positives. At least this shows the controls are working.

"What we have to do is handle it, carry on and do the right thing," Millar continued. "What we're doing with our team (adopting a clear anti-doping line and internal testing programme] I think is the future of the sport, along with CSC and Columbia and the other teams doing the same thing and going in the right direction.

"There will always be guys doing it the wrong way, but I think we are the majority; the guys doing it the other way are the minority now."