Say it ain't so.

Chael Sonnen has been informed by California State Athletic Commission that he flunked his drug test following his epic fight with Anderson Silva at UFC 117 back in August, according to Sherdog.com. 

Sonnen could not be reached for comment and the commission would not provide additional details on the actual illegal substance pumping through Sonnen's system in the report. However,"drugs of abuse" were ruled out, meaning that it was most likely of the performance-ehancing variety.

If these allegations are upheld, Sonnen could face a lengthy suspension, jeopardizing his rematch with "The Spider" early next year.

Sonnen, who railed against Lance Armstrong for his alleged use of steroids, now joins Josh Barnett and Sean Sherk on a lengthy list of fighters that the CSAC has fingered for illegal substances.

More on this breaking news as it happens.