Star sprinter Erriyon Knighton, who tested positive for a banned steroid earlier this year, has been cleared to compete in the upcoming U.S. Olympic track trials after an arbitrator ruled that the substance was ingested through contaminated meat, according to USADA.

Knighton, who won silver in the 200m at the 2023 World Championships and bronze in the same event in 2022, tested positive for trenbolone in an out-of-competition test in March this year. He was provisionally suspended following the positive test.

Following hearings on 14 and 16 June in which Knighton, USADA and other witnesses participated, an independent arbitrator ruled that the case should be treated as a "no fault" violation.

This ruling means that Knighton, despite testing positive, will avoid suspension and will be able to compete in the upcoming track and field trials.

"We did what the rules require us to do in all positive cases," USADA CEO Travis Tygart said in a statement. "We can be confident that justice was done and transparency was achieved as required by the rules."

The USADA statement said the arbitrator overseeing the case found that Knighton's positive sample was "most likely caused by the consumption of meat contaminated with trenbolone".

The agency described trenbolone as "a known cattle growth promoter that is legally used in beef cattle produced in and exported to the United States.

As Knighton's test was out-of-competition, there are no results to disqualify him, allowing him to retain his results.

The American sprinter, who was provisionally suspended on 12 April 2024, has had his suspension lifted as he was found not to be at fault and can return to competition immediately.

The athlete, who was born on 29 January 2004 in Tampa, Florida, will therefore be free to compete in the Olympic trials, which begin in Eugene, Oregon, on Friday, although the World Anti-Doping Agency (WADA) has said it may appeal, according to James Fitzgerald, WADA's director of media relations.