In 2003 he won his first race, when he finished just in front of Lennie Kristensen in the overall rankings of the Tour Down Under. He has taken part in all editions of the Tour de France since 2003, and won stage 16 of the 2009 Tour to record his second professional stage win in any competition (for the Euskaltel team), with his 9th position overall in 2007 as his next best attempt. His cousin Íñigo Chaurreau is also a professional cyclist.
On 26 June 2009 he tested positive on Recombinant Erythropoietin (EPO), for which he was suspended by the UCI on 31 July 2009.