Tour de France 2017: Chris Froome extends lead, Primoz Roglic wins stage

Britain's Chris Froome extended his lead in the Tour de France to 27 seconds at the end of a brilliant stage 17 won by Slovenia's Primoz Roglic.

Former ski jumper Roglic held his form brilliantly during a lengthy descent into the finish at Serre-Chevalier
Former ski jumper Roglic held his form brilliantly during a lengthy descent into the finish at Serre-Chevalier

Froome was third in a thrilling mountain stage during which Fabio Aru slipped from second to fourth overall.

Marcel Kittel, who led the green jersey contest, was forced to retire from the race after crashing early in the stage.

There are four stages remaining, with a potentially crucial summit finish in Izoard on Thursday.

Froome had lost time on the drag up to the mountain-top finish in Peyragudes on stage 12, and had the yellow jersey taken off him by Aru.

But the Team Sky leader, aiming for his fourth Tour victory and third in succession, reclaimed it on an uphill sprint to Rodez on stage 14.

Should any of his rivals want to ride into Paris on Sunday in the yellow jersey, they need to attack on the punishing slopes up to Izoard and hope Froome cracks because he is expected to take time off them during Saturday's time trial in Marseille.

In-form Colombian Rigoberto Uran and French favourite Romain Bardet are second and third in the standings - both 27 seconds behind the leader.