By Sandra Rose  | 

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Olympic track star Sha'Carri Richardson famously failed a drug test prior to the Olympics in 2020, and was not allowed to compete.

Richardson, 21, was favored to win a gold medal in the women's 100 meters at the 2020 Summer Games in Tokyo and had blown away her competition at the U.S. Olympic trials.

But her dreams of Olympic gold ended after she tested positive for cannabis.

Meanwhile, 15-year-old Kamila Valieva, a Russian who is favored to take home the gold medal in figure skating, was cleared to compete at the Beijing Olympics in China after she tested positive for the banned heart medication Trimetazidine.

Trimetazidine, an anti-angina medication that is prescribed for chest pain, is banned because it improves performance by increasing the heart rate. The International Olympic Committee ruled the banned drug gives athletes an unfair edge over their competition.

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Richardson noted the similarities between herself and Valieva — and that only one of them was cleared to compete.

"The only difference I see is I'm a black young lady," she tweeted on Monday.
 

The Court of Arbitration for Sport, which cleared Valieva to compete, said the teen's age was one of the factors in its decision and that banning her "would cause her irreparable harm."

Richardson and other American athletes were unsympathetic to Valieva's plight.

"You have athletes that are competing under two different systems, and we saw that today," tweeted former figure skater Ashley Wagner. "THAT is not fair, raise the age minimum so we can all play on the same terms. This is not the call," continued Wagner, who won a bronze medal with the U.S. team in 2014.