Italian cyclist Mauro Santambrogio faces a lifetime ban after testing positive for doping shortly before a previous ban expired.
The International Cycling Union says the 30-year-old Santambrogio tested positive for testosterone on October 22 and is provisionally suspended.
Santambrogio was serving an 18-month ban, which expired November 2, for using the blood-booster EPO while riding for Italian team Vini Fantini at the 2013 Giro d'Italia.
He was stripped of his win in a Giro mountain stage and disqualified from the race.
Santambrogio reportedly received a reduced 18-month ban this year after giving evidence to the Cycling Independent Reform Commission.
That panel was launched by new UCI leadership to investigate doping in the Lance Armstrong era and alleged complicity by the governing body. It is due to report in February.
