United States sprinter Erriyon Knighton has been handed a four-year ban after the Court of Arbitration for Sport partially upheld appeals from World Athletics and the World Anti-Doping Agency against a decision not to suspend him.
Knighton tested positive for trenbolone – a banned substance used for muscle growth – in March 2024 but avoided a ban following an independent arbitrator’s ruling and was cleared to compete at the 2024 Olympics.
The 21-year-old was not selected by the USA for the upcoming World Championships in Tokyo and his ban takes immediate effect.
Knighton, who finished fourth in the 200m in Paris last summer, submitted evidence claiming the adverse findings were due to meat contamination.
World Athletics and Wada found the evidence “fell short of the required proof of source” and was “statistically impossible”, and Cas has now ruled in their favour.
“The Cas panel determined that there is no proof that would support the conclusion that oxtail imported into the USA would be likely to contain trenbolone residues at the level required to have caused the athlete’s adverse analytical finding,” Cas said.
Meanwhile, Ethiopian middle distance runner Diribe Welteji will also miss the World Championships, which run between 13-21 September, after Cas upheld a provisional suspension while her doping case is heard.
The 23-year-old, who won 1500m silver at the 2023 World Championships in Budapest, was charged with failing or refusing to submit a doping sample by the Ethiopian Anti-Doping Authority in late August.
