Justin Gatlin has been denied the outright world 100m record after his time was suddenly altered almost a week after his blistering run in Qatar.
Officials have revealed the World and Olympic champion clocked 9.766 seconds, not 9.760 seconds as first thought.
According to IAAF rules, the time should have been rounded up to 9.77 secs - matching but not beating Asafa Powell's existing world record.
Powell eclipsed Tim Montgomery's old mark of 9.78 in Athens last year.
IAAF spokesman Nick Davies said: "The problem here was it was a mistake, but better we admit that.
"Obviously we're disappointed for Justin but he's talented enough to come right back and break it again."
In a statement issued through US Track and Field, Gatlin said: "It is very disappointing to me that it has taken five days to determine the official time of a race with this significance.
"I remain confident that I am the world's fastest man and I look forward to proving it once again. My parents raised me to be a good sport, but I don't want to share the world record."
Gatlin's agent Renaldo Nehemiah said: "This is just more incentive for Justin to go out and break the world record again officially.
"He is in excellent shape for this time of the year. That bodes well for him."
The IAAF said it acted after being informed of the error by Tissot Timing.
Gatlin and Powell will renew their rivalry when they go head-to-head for the first time this season at the Gateshead Grand Prix on 11 June.
The pair last met on the track at the London Grand Prix last July, when Gatlin cruised to victory as Jamaican Powell pulled up with a groin injury that also kept him out of the World Championships.