Olympic and world champion sprinter Justin Gatlin has revealed he failed a drugs test in April.
The American, who shares the 100 metres world record with Jamaican Asafa Powell, was informed by the United States Anti-Doping Agency that he had tested positive for 'testosterone or its precursors' after running a relay race in Kansas City on April 22.
The 24-year-old was a double world champion in Helsinki last year, at 100m and 200m, and is the reigning 100m Olympic champion after triumphing in Athens two years ago.
Gatlin, whose world record-equalling 100m time of 9.77secs was set in May, has fought an intense rivalry with Powell.
They have stood out as the world's leading sprinters this year.
Gatlin will protest his innocence, insisting he has not knowingly taken any performance-enhancing substance.
The New York athlete, who is coached by Trevor Graham and has sprint hurdles legend Renaldo Nehemiah as his agent, believes he can uncover the truth behind the failed test.
He has already vowed to give his full co-operation to the USADA, in what Gatlin hopes will be an investigation which clears his name.
