The United States' Olympic women's 100 metres hurdles champion, Brianna Rollins-McNeal, has been provisionally suspended by the Athletics Integrity Unit (AIU) for alleged tampering of doping control.
If found guilty, she could face a ban that will make her ineligible for the Tokyo 2020 Olympics and the 2022 World Athletics Championships.
The latter is to be held in her home country, in Eugene in Oregon.
McNeal, formerly known under her maiden name Rollins, is a world and Olympic champion in the women's 100m hurdles.
She notably won the Olympic gold medal in her event at the Rio 2016 Games, leading home an all-American podium with Nia Ali and Kristi Castlin.
Her sole world title victory came at the 2013 World Championships in Moscow, where she was joined on the podium by Australia's Sally Pearson and Britain's Tiffany Porter.
Her personal best of 12.26sec is also the fourth fastest time in the event's history.
McNeal was sanctioned after the AIU deemed she was "tampering within the results management process", as outlined in Article 2.5 of the World Anti-Doping Code.
She missed the 2017 World Championships after being handed a one-year ban for a whereabouts failure in 2016.
McNeal said at the time she forgot to update her details of her whereabouts and was attending a fete of honour in her hometown and travelling to the White House to meet former US President Barack Obama respectively.
McNeal is the latest American athlete to face potential sanctions for anti-doping violations following the recent case of men's 100m world champion Christian Coleman.
Coleman has been handed a two-year suspension for three whereabouts failures, meaning he is set to miss the Tokyo 2020 Olympics.
He is currently appealing this decision to the Court of Arbitration for Sport.
Triple jumper and reigning Pan American Games champion Omar Craddock is having his case investigated for a similar offence and is currently provisionally suspended too.