Sprinter Sha'Carri Richardson, who was suspended last week for a positive marijuana test, was left off the U.S relay team and won't compete in this year's Olympics, USA Track & Field said Tuesday.

Why it matters: While Richardson had accepted a one-month suspension, there was still a chance she could return in time to race in the women's 4x400-meter relay in Tokyo on Aug. 6. But USATF declined to add her to the team, saying it wouldn't be fair to the other athletes.

What they're saying: “While USATF fully agrees that the merit of the World Anti-Doping Agency rules related to THC should be reevaluated, it would be detrimental to the integrity of the U.S. Olympic Team Trials for Track & Field if USATF amended its policies following competition, only weeks before the Olympic Games,” USATF said in a statement Tuesday. 

• "So while our heartfelt understanding lies with Sha’Carri, we must also maintain fairness for all of the athletes who attempted to realize their dreams by securing a place on the U.S. Olympic Track & Field Team."

Richardson said last week she had been coping with her mother's death, as well as the pressure of participating in the trials, which led her to a state of "emotional panic."

• "Don't judge me, because I am human. ... I just happen to run a little faster," she added.