Usain Bolt tells reporters `` I 'm clean '' ahead of London Diamond League meeting . A six-time Olympic gold medalist , Bolt was speaking publicly for the first time since his fellow Jamaican and elite sprinter Asafa Powell and Tyson Gay of the United States tested positive for banned substances . The Jamaican sprinter is set to compete in the event on Sunday at Olympic Stadium in London. Gay and Powell both deny knowingly taking banned substances . A Jamaican international footballer fails a drugs test during a World Cup qualifier .
Usain Bolt tells reporters `` I 'm clean '' ahead of London Diamond League meeting . The Jamaican sprinter is set to compete in the event on Sunday at Olympic Stadium in London. Gay and Powell both deny knowingly taking banned substances . A Jamaican international footballer fails a drugs test during a World Cup qualifier .