The winner of the 2021 Boston Marathon could have her title stripped after allegedly testing positive for a banned substance.

According to the Athletics Integrity Unit, Kenyan marathoner Diana Kipyokei had metabolites of triamcinolone acetonide in her system.

Triamcinolone acetonide can reportedly enhance an athlete's performance.

The agency says Kipyokei’s sample was collected after the Boston Marathon was completed.

"The cases announced today are part of a recent trend in Kenyan athletics regarding triamcinolone acetonide, with ten Kenyan athletes testing positive for that prohibited substance between 2021 and 2022," the Athletics Integrity Unit said in a statement.

According to ESPN, Kipyokei faces a 4-year ban and losing her $150,000 Boston Marathon prize money.

Kipyokei has not publicly commented on the charges.