Horner takes lead in Tour of Spain

Radio Shack team rider Christopher Horner of the U.S. climbs during the 186km 18th stage of La Vuelta, Tour of Spain, cycling race from Burgos to Pena Cabarga September 12, 2013. REUTERS/Joseba Etxaburu

ALTO DE NARANCO, Spain (Reuters) - American Chris Horner took another step towards becoming cycling's oldest Grand Tour winner as he edged out Italy's Vincenzo Nibali from the Tour of Spain leader's jersey on Friday.

Fifth on the Alto de Naranco stage behind winner Joaquim Rodriguez of Spain as the front group of favourites split up close to the summit, Horner gained six seconds on ninth-placed Nibali.