Kenyan athlete Wilson Kipsang has been banned for four years.
The former marathon world record-holder has been found guilty of whereabouts failures, and of tampering with a doping control.
The 38-year-old Kipsang won the London Marathon in 2012 and 2014. He also won bronze at the London 2012 Olympics in the marathon.
Kipsang was provisionally banned in January 2020.
The Athletics Integrity Unit file on his case say he was guilty of four whereabouts failures.
He missed tests in April 2018, April 2019 and May 2019. He also had a 'filing error' regarding his whereabouts for a January 2019 test.
He was also charged with "providing deliberately misleading information and evidence to the AIU in his explanation for the missed tests dated 12 April 2019 and 17 May 2019 in an attempt to obstruct or delay the investigation into those missed tests and/or to prevent normal procedures from occurring."
In his defence, Kipsang emphatically stated that he has never used prohibited substances, and emphasised that none were found in this case.
Kipsang's is the latest incident of anti-doping rule breaches emanating from Kenya.
In 2019, fifteen Kenyan athletes were banned for anti-doping violations.
Speaking with The Guardian in 2015, Kipsang claimed "maybe 99%" of Kenya's athletes can be trusted.
"There are great measures under way now in Kenya to protect the sport," Kipsang said.
"We have seen that many athletes don’t understand what is doping and so we are trying to create awareness and find out how they fall prey in this situation.
"The ban has been increased from two years to four years, which will also act as a deterrent."
He now finds himself banned for four years and his international athletics career likely over.
The Kenyan will be two months shy of his 42nd birthday when eligible to run again.