Chris Froome appears to be living a charmed life at the 100th Tour de France after he suffered a sugar crash, took a time penalty, and increased his lead regardless on yesterday's double ascent of the Alpe d'Huez.

Froome was docked 20 seconds for an illegal feed inside the final five kilometres of the stage, showing his first signs of distress all Tour when he waved for help and team-mate Richie Porte fetched him an energy bar.

Both riders were penalised for the move - an apparent attempt to have Porte take the hit for returning to the team car - but it only hurt Froome so much with closest rival Alberto Contador more than a minute back down the road.

"It's not the first time in my career I've run out of sugar," said Froome, who now leads Contador by five minutes 11 seconds. "It's a horrible feeling. I'm just happy to get through the stage and come out of it with more of an advantage than I went in with.

"If that was a bad day for me then I'll definitely accept that."

"If that was a bad day for me then I'll definitely accept that" - Chris Froome

It was not all good news, though, as the dangerous Nairo Quintana, who had been with Froome when he ran into difficulty, raced ahead to cut his own deficit to the yellow jersey to five minutes 32 seconds.

Up ahead, Christophe Riblon had become the first French stage winner of this 100th Tour de France, the last surviving member of a breakaway winning by 59 seconds after catching and dropping Tejay Van Garderen less than two kilometres from the finish.

When he saw his chance, he did not merely slide past the American but burst clear.

"I wanted him to know in his mind that he had no chance," the 32-year-old said. "This is a huge thrill."

Attention now turns to today's 204km stage from Bourg-d'Oisans to Le Grand-Bornand.

If yesterday's double ascent of the Alpe d'Huez was unprecedented, things get no easier today on this long stage featuring two hors categorie climbs - one immediately after the start - as well as two further category one climbs and a category two.

Garmin-Sharp veteran David Millar revealed his team-mate Ryder Hesjedal, last year's Giro d'Italia winner, had branded the stage "THE REDONKATHON" and identified it as perhaps the toughest day of a Tour which has already visited Mont Ventoux as well Alpe d'Huez - twice.

Although Froome escaped his dramas yesterday without serious damage, he will have to be on his game again today with the challenges coming thick and fast.

"I have eaten a bowl of rice and a recovery bar and had a lot of fluid," he said right after yesterday's stage. "We'll just have to see how I am tomorrow."