Young Spanish rider Alejandro Valverde quit the Tour de France [Images] midway through an uneventful 13th stage between Miramas and Montpellier on Friday.

The 24-year-old who beat race leader Lance Armstrong [Images] in a sprint finish in Tuesday's mountainous 10th stage at Courchevel fell to the rear of the peloton suffering with a knee injury.

Valverde began the day fifth in the overall standings and was wearing the white jersey as the leading young rider.

Armstrong, favourite to clinch a seventh Tour victory, was safely tucked into the peloton with 75km of the 173.5-km stage left, four minutes behind a five-man escape group.

Of the five stage leaders American Christopher Horner was the best placed in the overall standings, 15 minutes behind Armstrong in 29th place.

The lead had stretched to nine minutes at one point, although the peloton, led by the Davitamon-Lotto and lampre-Caffita teams, were expected to reel them in before the end of the generally flat stage.