Image 1 of 3 Carlos Barredo (Image credit: Xander van Ommen Photography) Image 2 of 3 Carlos Barredo (Rabobank) (Image credit: Bettini Photo) Image 3 of 3 Podium: Lieuwe Westra (Vacansoleil), Tony Martin (Omega Pharma Quick Step), Carlos Barredo (Rabobank) (Image credit: Photopress.be)

Carlos Barredo has announced his retirement from cycling. The Spaniard is under investigation for violations of the biological passport programme. Rabobank suspended him earlier this year and his contract ended this season.

His problems started in May 2011 when he was given a top ranking of 10 on the UCI's “suspicious list” which ranked all the starters of the 2010 Tour de France and gave their individual scores on suspicion of doping. Those scores were based on the riders' individual biological passport values up to the event, and included the readings of the first blood test performed just before the start of the 2010 Tour.

The 31-year-old earlier this year received a letter from the UCI concerning the fluctuations in his blood values, and he responded, proclaiming his innocence, Rabobank said. His last race for the team was the Criterium du Dauphine in June. He then broke some ribs in a training accident and the team said it would withhold him from racing until the matter was cleared up.

In October the UCI formally requested that the Spanish cycling federation open disciplinary proceedings against Barredo and the team suspended him.

“I will not return to the bicycle,” Barredo told El Pais. “On Wednesday I start my new job,” for a coffee-making company.

Barredo won a stage at the Vuelta a Espana in 2010, and won the Clasica de San Sebastian in 2009, finishing second there in 2011. However, he is perhaps best known for attacking Rui Costa with his front wheel after stage six of the Tour de France 2010.