WBC postpones Wilder-Povetkin fight after failed drug test (The Associated Press)

Heavyweight champion Deontay Wilder’s title defense against Alexander Povetkin has been postponed by the WBC after the Russian challenger failed a drug test. The WBC says the May 21 fight in Moscow is off, pending an investigation, with no backup date. Povetkin’s promoter has said the substance found in an April test was meldonium, the stamina booster for which tennis star Maria Sharapova and dozens of other athletes in ex-Soviet nations have tested positive since it was banned from Jan. 1.