Former Jamaican sprinter Raymond Stewart has denied any involvement with performance-enhancing drugs.

Stewart, 43, was implicated by witness Angel Heredia in the ongoing case to prosecute coach Trevor Graham for supplying athletes with illicit substances.

The former world championship silver medallist over 100 metres, pictured here as an athlete 15 years ago, was accused by Heredia of accepting drugs that he then gave to up-and-coming athletes.

"Actually that was speculation, what [the prosecutor] wrote in the paper," Stewart claimed. "I already talked to him and let him understand that the email [Heredia] sent - despite people telling me 'this is what I need to do' - that I always reject these things."

Stewart currently coaches 2007 Pan American Games silver medallist and world championship finalist Marvin Anderson.

As a sprinter he took silver at the 1987 Rome championships and also won a silver medal in the 1984 Los Angeles Olympics as part of the 4x400m relay team.

Mexican athlete and nutritionist Heredia - who also claimed that Maurice Greene was a user of the designer steroids that he supplied to coaches and athletes - was giving evidence for the case to indict Graham.

Jamaican coach Graham blew the whistle on the BALCO laboratory in June 2003 when he sent a used syringe containing THG to the United States Anti-Doping Agency.

Several of Graham's athletes have tested positive for drugs, including Olympic champion Justin Gatlin, who was stripped of his 100m world record after being handed an eight-year ban which was reduced to four on appeal.

Reda Maher / EME / Eurosport