The Tour de France is now Lance Armstrong's to lose. The verdict of the first mountain stage through the Alps and into Italy yesterday was pitiless - for the opposition. The Texan won his third stage out of nine and now leads by a margin which, on paper at least, should make him untouchable.

Armstrong is always at his best in foul weather - "it eliminates 50 per cent of the opposition because they get bad morale and things go wrong for them," he explained - and yesterday the cloud hung low, the thunder boomed and the rain poured down. At almost 9,000 feet on top of the Col du Galibier, the highest point of this Tour de France, it was bitterly cold.

Armstrong and his team were untested when it came to defending a race lead across such terrain, but they passed with flying colours among the scree slopes and dirty snowdrifts of the Galibier. The climbers duly attacked, led by France's Richard Virenque, and the Spaniard Fernando Escartin, but the mountain belonged to North America, for the first time in the Tour's 96-year history.

From defence, Armstrong switched to attack at the foot of the six-mile climb to the finish here. With a brief, brutal effort, he left the rest of the small group with whom he had crossed the Italian border at the Col de Montgenevre, and caught up with Escartin and the Giro d'Italia winner Ivan Gotti, who had slipped away on the descent from the customs post.

They could not live with him, and nor could the Swiss Alex Zulle, who was the only contender to limit his losses as the American forged ahead, only showing the strain in the final two miles. Had the Swiss not crashed last Monday, he would now be in a position to challenge for victory.

Armstrong's closest challenger is now the Basque Abraham Olano, who is just over six minutes behind, but Olano showed yesterday he is not able to match the American in the mountains.

Virenque at least had the compensation of taking the King of the Mountains jersey; he may not be loved by his fellow cyclists or the media, but he has achieved part of what he came here for.

The green jersey also changed ownership, and is now on the shoulders of the Australian Stuart O'Grady, after the mountains proved too much for the top two riders in the rankings, the Estonian Jaan Kirsipuu and Mario Cipollini. Cipollini fell off on a rainsoaked descent and was taken to hospital.