Another of the favourites for this year's Tour de France has been forced to abandon the race.

Two-time winner Alberto Contador has retired after a heavy crash during stage 10.

The Spaniard attempted to regain his place in the peleton after the fall, but he was eventually forced to quit and climb into his team car.

It is the second high-profile retirement of this year's race after defending champion Chris Froome had to withdraw last week.