Operación Puerto doping case
He was linked to Operación Puerto doping case. After he was initially named in the investigation, Sevilla was still able to ride and won the Vuelta a Asturias. On the day before the 2006 Tour de France, Ullrich and Sevilla were explicitly linked to the investigation and not allowed to start the race. On 20 July 2006, Sevilla was fired from T-Mobile in relation to the aforementioned accusations.