Italian race walker Alex Schwazer has been provisionally suspended by the International Association of Athletics Federations (IAAF) after his B-sample came back positive.
The 2008 Olympic 50 kilometres race walk gold medallist tested positive for testosterone following the re-test of a urine sample taken on January 1 but details only emerged on June 22.
Analysis on the B-sample was carried out on Tuesday (July 5) at the World Anti-Doping Agency-accredited laboratory in Cologne.
“The IAAF confirms it has provisionally suspended Alex Schwazer after the B sample confirmed the positive finding of the A,” the IAAF confirmed to insidethegames.
“The athlete will be offered an expedited hearing prior to the Rio Olympics.”
Schwazer had only returned to competition in May following the completion of a drugs ban after testing positive for erythropoietin before London 2012.
The 31-year-old had admitted his offence four years ago but this time claims he is innocent and is the victim of a conspiracy.
His lawyer Gerhard Brandstätter claimed yesterday that the results of the positive test were known on May 13, but it was more than a month later before Schwazer was informed.
He argued that an investigation into the drugs test be suspended until after the Olympic Games in Rio de Janeiro next month.
Schwazer claimed a shock victory at the IAAF World Race Walking Team Championships in Rome in May, beating Australian Jarred Tallent into second place by more than three minutes.
The Italian could face the prospect of being stripped of the title should he be banned after the hearing, which would also rule him out of the Olympic Games.
Tallent was awarded the Olympic gold medal from London 2012 last month after the results of original winner, Russia's Sergey Kirdyapkin, were annulled because of doping.
Tallent had also finished second behind Schwazer at Beijing 2008.