Tour de France: Richie Porte, the pre-race favourite, suffers heavy crash

Froome suffered a mechanical problem on the Mont du Chat, the last of three hors categorie climbs on the day, and as the three-time Tour victor was calling for the team auto Aru attacked in a clear breach of cycling's protocol.

Tour de France doctor Florence said Porte had spoken after the fall but that the extent of his injuries would not be known until after X-rays.

Colombian Rigoberto Uran (Cannondale-Drapac) won Sunday's dramatic stage, a 181.5-kilometre route from Nantua to Chambéry.

Britain's Geraint Thomas has been forced to abandon the Tour de France after crashing on stage nine.

He crashed twice while wearing the yellow jersey, on stages two and four, and on Saturday went straight into a hay bale after he and Froome took a corner too fast on a descent during stage eight to Station des Rousses.

It was a thrilling finish to a remarkable stage, but the nasty crashes for Thomas and Porte took the shine off the day's racing.

However, organisers said he was conscious and speaking but was being taken to hospital.

Thomas also crashed out of the Giro d'Italia in May - caused by a police motorbike - on stage nine, when he was Team Sky's race leader.

Porte crashed on the descent from the Mont du Chat, the last of the day's big climbs, as he slid off the inside of corner and was violently flung across the road, with Quick Step Floors rider Dan Martin unable to avoid him.

However, he has lost his rear-gunner as Thomas started the day second overall.

There was also drama on the climb of the Mont du Chat when Froome took exception to Aru making a move when the defending champion had to stop for a mechanical before the Brit's rivals sportingly slowed down.

Five riders in total crashed out of the race on Sunday while two-time former victor Alberto Contador was able to carry on quickly after coming down on an uphill section. "I want to thank the other riders, who did not attack".

  • Marlene Weaver