The Union Cycliste Internationale (UCI) has started a disciplinary procedure against Spanish rider Carlos Barredo after irregularities were found in his blood profile, part of the UCI’s biological passport anti-doping monitoring system.

Barredo has ridden for the Dutch Rabobank team for the past two seasons. His last major win was a stage of the Vuelta a Espana in 2010 whilst riding for QuickStep. Prior to that, he had victories in Clasica de San Sebastian (2009), and stages of Paris-Nice (2008), the Tour Down Under (2006) and Vuelta a Asturias (2004).

In August, Rabobank issued a statement saying that Barredo had been questioned by the UCI for biological passport anomalies relating to 2007-2011. At that point, Barredo stressed that he had never doped nor used blood transfusions.

“The rider shall be accorded the right to the presumption of innocence until a final decision has been made on this matter,” said the UCI on Thursday.

The UCI’s biological passport system builds up a profile of an individual rider’s blood and urine values. Any unexpected or unnatural fluctation in these values – which include haematocrit and hormone levels – can be a sign that a rider is using banned performance-enhancing substances or blood transfusions.