Alessandro Petacchi, the Italian cyclist who produced a suspicious urine sample when tested for doping at the Giro D'Italia in May, attended a hearing at the headquarters of the Italian Olympic Committee (CONI) in Rome on Monday.
The 33-year-old Italian sprinter was quizzed by Ettore Torri, CONI's anti-doping prosecutor, for two hours as he attempted to clear his name.
Petacchi hopes to prove his innocence so that he can take his place at the Tour de France, which starts next Saturday.
"I tried to explain that I acted in good faith," Petacchi said after the hearing.
Asked if he felt confident that he would be at the Tour de France, he replied: "It depends on the prosecutors."
Torri, who is also interviewing Gianluigi Stanga, team manager of Petacchi's Milram team, promised a swift decision on Petacchi.
"It will be done very quickly," Torri said.
Petacchi delivered a 'non-negative' doping test after the third of his five stage wins at Pinerolo on May 23, with his sample showing an unusually high level of salbutamol, a substance primarily used to treat asthma.
Salbutamol is a banned substance but riders suffering from asthma are allowed restricted use of the drug if they can provide a medical certificate.
Petacchi does have such a certificate, having suffered from asthma for many years.
If found guilty of cheating, the Italian could be banned from cycling for two years.
Petacchi's urine sample taken at Pinerolo was the only one of the five doping tests he gave that showed an excessive amount of salbutamol.