The UFC announced Thursday that new signee Amanda Ribas would be out of her strawweight fight at The Ultimate Fighter 25 Finale due to a potential USADA anti-doping violation.

On Friday, Ribas denied any use of performance-enhancing drugs in a statement obtained by MMA Fighting and posted on her Instagram. The Brazilian fighter, who has yet to compete in the UFC, said in her career in MMA, judo and Brazilian jiu-jitsu, she “never made use of any illegal substance.”

“And I did not use anything now,” Ribas wrote. “I have no idea as to the origin of my positive test with USADA.”

Ribas, who trains out of American Top Team in Florida, failed a drug test stemming from a sample collected June 7. She was supposed to face Juliana Lima on the July 7 card in Las Vegas. The Nevada Athletic Commission (NAC) has been looped into the doping case by USADA and will also have jurisdiction.

USADA, the UFC’s anti-doping partner, does not release the name of the banned substance that showed up in the test until after the adjudication process or if the athlete reveals it himself or herself.

Ribas’ full statement is below: