LAS ROZAS, Spain (AP) — Alberto Contador maintained the overall lead at the Spanish Vuelta on Thursday while Imanol Erviti of Caisse d'Epargne won the 18th stage.

Contador, aiming to complete a sweep of the three major cycling crowns after winning the 2007 Tour de France and the Giro d'Italia this year, maintained his lead of 1 minute, 17 seconds over Astana teammate and Rowland Hall graduate Levi Leipheimer of the United States.

Erviti overtook Irish rider Nicolas Roche of Credit Agricole in the final moments to win the 104-mile stage from Valladolid in 3 hours, 53 minutes, 17 seconds. Spanish rider David Herrero of Xacobeo-Galicia was 1 second behind in third.

Contador is aiming to join a short list of cyclists that won the Tour de France, the Giro d'Italia and the Vuelta. The Spanish cyclist finished 7:29 back of Erviti.

The 19th stage today includes two mountain climbs. The time-trial is Saturday before the ride ends in Madrid on Sunday.