World champion sprinter Christian Coleman is set to miss next year's Tokyo Olympics after being banned from athletics for two years for anti-doping violations, the Athletics Integrity Unit (AIU) announced on Tuesday.
The American, who won the men's 100 metres at last year's World Championships in Doha, was provisionally suspended for three 'whereabouts failures' in June.
World Athletics' Disciplinary Tribunal upheld the charge and banned Coleman for two years, backdated to 14 May, 2020.
The 24-year-old has 30 days to appeal against the decision at the Court of Arbitration for Sport.
He is set to miss next year's Olympic Games in Japan, where he would have been among the favourites to win 100m gold.
Coleman, who is also the 60m world record holder, only ran in the 4x100m relay heats in his first Olympic appearance in Rio de Janeiro four years ago.
The AIU charged Coleman for missed tests in January and December 2019, as well as for a "filing failure" last April.
To prove an anti-doping violation, an athlete has to have committed three whereabouts failures within 12 months.
Coleman previously escaped suspension on a technicality ahead of last September's World Championships.
Those three whereabouts failures were recorded on June 6, 2018, January 16, 2019 and April 26, 2019.
However, Coleman had successfully argued that the first missed case should have been backdated to the first day of the quarter -- April 1, 2018 -- meaning the three failures fell just outside the required 12-month period.
But now the missed test on December 9, 2019, added to the two failures in January and April, have seen Coleman suspended.
"I think the attempt on December 9th was a purposeful attempt to get me to miss a test," Coleman said after he was charged in June.
"Don't tell me I 'missed' a test if you sneak up on my door -- parked outside the gate and walked through... there's no record of anyone coming to my place -- without my knowledge."
Two-year suspensions can be reduced to one year if there are mitigating circumstances, but the tribunal rejected any chance of a reduction.
"We regret to say that we do not think there is any mitigation which can fairly be relied upon to reduce the sanction from the two-year period," the tribunal said in its findings.
"Unfortunately, we see this case as involving behaviour by the athlete as very careless at best and reckless at worst."
Coleman's suspension comes a week after doping charges brought against Bahrain's women's 400m world champion Salwa Eid Naser were dismissed.
- 'More than ready' -
In June, Coleman said testers had visited when he was out shopping for Christmas presents nearby, verifiable by bank statements and receipts.
"I was more than ready and available for testing and if I had received a phone call I could've taken the drug test and carried on with my night," he said.
"I was only made aware of this attempted drug test the next day on December 10th, 2019 by the AIU when I got this failed attempt report out of nowhere."
The report from the doping control officer posted by Coleman said the tester had arrived at his apartment and had failed to get a response after "multiple, loud knocks were made every 10 minutes" for an hour.
A doorbell next to Coleman's door was pressed but no ring could be heard. No attempt to reach Coleman by phone was made, according to the document.
"I've been contacted by phone literally every other time I've been tested," Coleman said. "Literally. (I don't know) why this time was different. He even said he couldn't hear the doorbell so why wouldn't you call me?"
Coleman last competed at the US Indoor Championships in February, running a world-leading 6.37 seconds in the 60m, just three hundredths of a second slower than his world record.
He also posted the best 100m time last year -- the 9.76sec he ran to win the world title.