His coach now says hes been "sabotaged".
http://news.bbc.co.uk/sport1/hi/athletics/5228246.stmJustin Gatlin's coach Trevor Graham claims the World and Olympic 100m champion has been "set up" after the sprinter failed a drugs test.
Athletics was rocked by the 24-year-old American's announcement that he tested positive for testosterone after a race in Kansas City in April.
Gatlin has denied knowingly taking performance-enhancing drugs.
And Graham said: "Someone has sabotaged my athlete. We know who but Justin did not take any banned substances."
Gatlin should be banned for life - Doyle
The sprinter made the unusual decision to announce the positive test himself before the US Anti-Doping Agency made the news public.
Gatlin, who took a share of the 100m world record in May - one month after his positive test - when he tied Jamaican Asafa Powell's mark of 9.77 seconds, insists he is innocent.
Throughout his career Justin has made clear his willingness to take responsibility for his actions
Craig Masback
USA Track & Field
"I cannot account for these results because I have never knowingly used any banned substance or authorised anyone to administer such a substance to me," he said.
Graham, who also coached the disgraced former world record holder Tim Montgomery, was the whistle-blower who launched the Balco steroid investigation in California and his claims of "sabotage" have yet to be investigated.
Gatlin's revelation comes just two days after Tour de France winner Floyd Landis' positive test for unusual levels of testosterone.
The American cycling star claims his body's natural metabolism caused the positive test but Gatlin's case is different.
The sprinter underwent a carbon-isotope ratio test which can determine whether the testosterone in a person's system is natural or unnatural.
Join world record holder Justin Gatlin
Gatlin's time was later revised to 9.77 the same mark as rival Powell
Gatlin, who won his Olympic gold in Athens two years ago, admitted he has tested positive for "testosterone or its precursors" that have come from an exogenous, or outside, source.
USA Track & Field executive director Craig Masback expressed his shock at Gatlin's positive test.
"Justin has been one of the most visible spokespersons for winning with integrity in the sport of track and field," he said.
"Throughout his career Justin has made clear his willingness to take responsibility for his actions."
Gatlin tested positive in 2001 for an amphetamine contained in medicine he had been taking for 10 years to treat attention deficit disorder.
The New York-born athlete was initially given a two-year ban but was reinstated in July 2002 because the amphetamine came from a prescription for a medical condition.
But it was made clear to him that another positive test could result in a lifetime ban.
And on Sunday the International Association of Athletics Federations restated that Gatlin would be banned for life if the test result is confirmed by the US authorities.
US Olympic Committee chief Jim Scherr admitted Gatlin's revelation "points out how insidious the problem of doping in sport has become".
Anyone accused of a doping violation has a right to have his or her case determined on the evidence
Terry Madden
US Anti-Doping Agency
Scherr added: "While this news is disappointing, it underscores the commitment we have made to protect the integrity of sport through clean competition.
"No one, regardless of their stature, is above the system."
Gatlin, arguably the biggest star in world athletics and certainly the American poster boy for the sport, can present the findings to an independent review board. After that he would still have the right to appeal.
US Anti-Doping Agency (USADA) chief executive Terry Madden said: "USADA will not comment on the facts of any active case.
"Anyone accused of a doping violation has a right to have his or her case determined on the evidence through the established process and not on any other basis.
Gatlin, who came to the track after a background in American football, became only the fifth man to add the world title to an Olympic 100m gold when he won the global crown in Helsinki last year.
He also won the 200m world title - only the second man to claim the World sprint double - to place himself among a very select group of athletics greats.
His world record came after failing the drugs test.
― Brigadier Lethbridge-Pfunkboy (Kerr), Sunday, 30 July 2006 10:14 (nineteen years ago)