Rigoberto Uran sprinted to a dramatic victory in a brutal ninth stage of the Tour de France and Chris Froome increased his overall lead after Richie Porte and Geraint Thomas crashed out of the race.

Uran got the verdict in a photo finish to what was an action-packed Sunday, denying Warren Barguil a stage win in his homeland by the narrowest of margins in Chambery.

Cannondale rider Uran came up with one final burst at the end of a gruelling 181.5 kilometres route from Nantua, which included three Hors Category climbs, and is now fourth in the general classification standings - with 55 seconds to make up on Froome.

Froome stretched his advantage to 18 seconds after crossing the line in third and it is now Fabio Aru – who finished fifth in a group of six battling it out for the stage win – who is his nearest rivals in the GC standings.

Porte's hopes of taking the title off Froome were ended when the BMC Racing rider suffered a horrific fall after losing control on the descent of the Mont du Chat.

The Australian went slightly off the narrow road and crashed across the surface into a rock on the other side of the road, taking out Dan Martin in the process.

A stricken Porte was treated by doctors before being carried into an ambulance and taken to hospital, while Martin picked himself up and finished the stage despite going down for a second time.

Thomas started the day 12 seconds adrift of Team Sky team-mate Froome in second spot in the GC standings, but his race was ended when he damaged his shoulder in a fall.

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.