Kingston (Jamaica), Jan 8 (IANS): Jamaican sprinter Sherone Simpson, who tested positive for a banned stimulant last June, passed the buck to her physical trainer when facing a disciplinary panel here.

The 29-year-old Olympic 4x100-relay gold and 100m silver medallist, insisted Tuesday that she was not a "cheat" and testified that she believed one of six supplements provided by trainer Christopher Xuereb of Canada was responsible for her positive test, reports Xinhua.

The sprinter said she was familiar with most of the supplements received from Xuereb except the Epiphany D1 on which she researched online for several hours before starting to take it but nothing she found raised "a red flag or an alarm bell".

Former 100-metre world record holder Asafa Powell, tested positive for the same stimulant at the National Championships last June, also believed the new brand of nutritional supplements given by Xuereb was to blame while he shared the same physical trainer with Simpson.

However, Xuereb in June has said that he didn't give Simpson or Powell any performance-enhancing drugs and only purchased major brand vitamins and "both athletes are clearly looking for a scapegoat".

Both athletes were provisionally suspended after returning with the positive test and missed the World Championships in Moscow, Russia, last August and will face a ban from the sport if found guilty of doping violation.

Simpson's hearing before the disciplinary panel is expected to last at least two days and later it will be Powell's turn.

Last year, several high-profile Jamaican athletes tested positive for banned substances at the World Championship trials, casting greater scrutiny on drug-testing practices in the world's sprinting powerhouse.