LAS VEGAS, Nev. - Tim Means will be unable to fight in the main event of the UFC show in Pittsburgh on Feb. 21 due to a potential doping violation.

The UFC announced Wednesday that Means has been notified of the potential out-of-competition violation by the U.S. Anti-Doping Agency, which administers the UFC's doping policy.

Means was scheduled to fight Donald Cerrone at the Consol Energy Center. The UFC says it will announce a replacement opponent for Cerrone shortly.

Means is a veteran welterweight better known as "Dirty Bird" with five wins in his last six fights.

He briefly reacted to the news on Twitter, saying, it "came out of left field."

The UFC won't sanction Means until its review policy is completed, but the promotion can't complete the review before the Pittsburgh show.