Junior dos Santos has been pulled from UFC 215 and is facing a suspension.

The former UFC heavyweight title holder was set to take on Francis Ngannou inside the Rogers Place in Edmonton, Alberta on Sept. 9. Instead, Ngannou is left without an opponent although a replacement search has begun.

An Aug. 10 sample caused dos Santos to be flagged. Not much else has been confirmed at this time. You can read the UFC’s statement below:

“The UFC organization was notified today that the U.S. Anti-Doping Agency (USADA) has informed Junior Dos Santos of a potential Anti-Doping Policy violation stemming from an out-of-competition sample collected on Aug. 10, 2017. Because of the proximity to Dos Santos’ upcoming scheduled bout at UFC 215 in Edmonton, Canada against Francis Ngannou, Dos Santos has been removed from the card and the UFC is currently seeking a replacement.

USADA, the independent administrator of the UFC Anti-Doping Policy, will handle the results management and appropriate adjudication of this case involving Dos Santos. Under the UFC Anti-Doping Policy, there is a full and fair legal process that is afforded to all athletes before any sanctions are imposed. Additional information will be provided at the appropriate time as the process moves forward.”