The International Olympic Committee (IOC) has rejected Sha'Carri Richardson's accusations of double standards.
The American sprinter was banned from competing in the Tokyo Olympics last summer after she tested positive for marijuana.
Now, the star athlete has called out the IOC on social media, after Russian teenager Kamila Valieva was permitted to continue competing in the Winter Games despite failing a drug test at Christmas.
Richardson - who was a top contender in the women's 100m - took to Twitter last week to compare her situation to Valieva's. The 15-year-old figure skater tested positive for trimetazidine on Christmas day, but her test result only surfaced after she had begun competing in the Beijing Winter Games.
Despite her failed drug test, the Court of Arbitration for Sport (Cas) ruled that Valieva - who is the star of the Russian women's figure skating team - could continue to compete.
Richardson took to Twitter in protest, writing: "Can we get a solid answer on the difference of her situation and mine? My mother died and I can’t run and was also favored to place top 3. The only difference I see is I’m a black young lady. It’s all in the skin."
Now, IOC spokesperson Mark Adams has responded to Richardson's accusation, claiming that her case and Valieva's have "nothing in common", per Independent.
"You can’t talk about double standards in relation to Russian and American athletes, each case is individual," Adams said. "Richardson’s positive doping test was discovered on 19 June, and the result was received before the start of the Olympics."
"She was suspended for a month. There is nothing in common between these two cases," he added.
He went on to express concern for Valieva, saying: "This Games, which has not concluded, concerns an issue in December. She is in the center of a lot of speculation. It must be very tough for her."
"We of course are in touch with the team, her welfare is the team’s first priority, and obviously we are very careful of that but there’s only so much that we can do," Adams added.