July 2 (UPI) -- U.S. track star Sha'Carri Richardson, an Olympic qualifier, was suspended due to a positive test for marijuana and could miss the Summer Games in Tokyo, the United States Anti-Doping Agency announced Friday.
Richardson confirmed the positive result Friday morning in an appearance on NBC's Today show. The USADA said she accepted a one-month ban from competition.
The positive test invalidated Richardson's win in the women's 100-meter race at the U.S. track and field trials in May, which punched her ticket to Tokyo.
"I want to take responsibility for my actions," Richardson told Today. "I know what I did and know what I'm supposed to do and I still made that decision. I'm not making an excuse or looking for any empathy."
Richardson, 21, admitted that she ingested the marijuana after she found out her mom died a few days before the trials.
"The rules are clear, but this is heartbreaking on many levels; hopefully, her acceptance of responsibility and apology will be an important example to us all that we can successfully overcome our regrettable decisions, despite the costly consequences of this one to her," USADA CEO Travis T. Tygart said in a news release.
Richardson's ineligibility started Monday. The USADA said her suspension was reduced "because her use of cannabis occurred out of competition and was unrelated to sport performance, and because she successfully completed a counseling program regarding her use of cannabis."
It remains unclear if Richardson can still compete in relays at the Summer Games -- events that occur after her ineligibility period.
"Beyond the one-month sanction, athlete eligibility for the Tokyo Games is determined by the United States Olympic & Paralympic Committee and/or USA Track & Field eligibility rules," the USADA said.
Americans Jenna Prandini and Gabby Thomas finished fourth and fifth, respectively, in the 100-meter race at the trials and will move up a spot in the standings if the disqualification stands. Prandini would join the three-woman U.S. team and compete in Tokyo. Thomas would serve as an alternate for the event.
Richardson was expected to compete in the 200-meter event at a Diamond League meet Sunday in Sweden, but was not on the entry list Thursday.
Javianne Oliver and Teahna Daniels qualified with Richardson for the women's 100-meter race. Trayvon Bromell, Ronnie Baker and Fred Kerley qualified for the U.S. men's team for the 100-meter race.
The postponed 2020 Summer Games run from July 23 to Aug. 8 in Tokyo.