Sha'Carri Richardson won't run in Tokyo Olympics

American sprinter Sha'Carri Richardson won't be headed to the Tokyo Olympics, after USA Track & Field announced she would not be selected for the 4 x 100-metre relay.

Richardson was expected to be one of the biggest draws at the upcoming Games, but was barred from the 100 metre race after testing positive for cannabis use, wiping out her victory at the U.S. Olympic trials last month.

After her suspension, fans hoped she would be chosen to compete in the relay event.

Coaches and USA Track & Field can select two runners on top of the first four trials finishers, but chose not to allow Richardson to compete.

In a statement, USA Track & Field wrote "All USATF athletes are equally aware of and must adhere to the current anti-doping code, and our credibility as the National Governing Body would be lost if rules were only enforced under certain circumstances."

Richardson said in an NBC interview last week that she used the banned substance to cope with the death of her mother, but took responsibility for breaking Olympic rules.

Her agent did not immediately respond to a request for comment.

USA Track & Field said the World Anti-Doping Agency would reevaluate its rules regarding THC, the main active ingredient in cannabis.