Great Britain were Friday stripped of the silver medal they won in the menâ€™s 4Ã—100 meters relay at last yearâ€™s Tokyo Olympics after CJ Ujah was found to have committed a doping violation.
Ujah tested positive for the prohibited substances ostarine and S-23, commonly used to build muscle, after the race on August 6.
The British team finished second behind gold medallists Italy in Japan by one-hundredth of a second.
As a result of their disqualification, Canada are expected to be awarded silver, with China promoted to the bronze-medal position.
A statement from the Court of Arbitration for Sportâ€™s anti-doping division said Ujah was â€œfound to have committed an anti-doping rule violationâ€.
â€œUjah is sanctioned with the disqualification of his results in the 4x100m sprint relay finalâ€¦ together with the forfeiture of any medals, diplomas, points and prizes,â€ it added.
CAS said World Athletics should consider any further action within its own jurisdiction, including a decision on the length of any ban.
Ujah said in a statement that he accepted the decision with â€œsadnessâ€ but claimed he had â€œunknowingly consumed a contaminated supplementâ€.
The 27-year-old apologised to his teammates, Zharnel Hughes, Nethaneel Mitchell-Blake and Richard Kilty.
â€œI would like to make it clear that I unknowingly consumed a contaminated supplement and this was the reason an anti-doping rule violation occurred at the Tokyo Olympic Games,â€ Ujah said in a statement.
â€œI would like to apologise to my teammates, their families and support teams for the impact which this has had on them.
â€œIâ€™m sorry that this situation has cost my teammates the medals they worked so hard and so long for, and which they richly deserved. That is something I will regret for the rest of my life.â€
Team GBâ€™s medal haul in Tokyo now drops to 64, one fewer than they achieved at London 2012.
â€œWe are incredibly disappointed that we find ourselves in this position today,â€ the British Olympic Association said in a statement.
â€œWe have always been unequivocal and consistent in our stance against doping.
â€œAll athletes, wherever they are from, deserve to go to the start line knowing they are in clean competition. It is with deep sorrow that colleagues and opponents of Ujah were not able to be reassured of this fact in Tokyo.â€