Anthony Joshua vs. Alexander Povetkin announced for Sept. 22 at Wembley Stadium. WBA Super, IBF, WBO and IBO heavyweight champion Anthony Joshua’s next fight won’t be against WBC champion Deontay Wilder after negotiations reached an impasse. Instead, Joshua will defend his titles next against Alexander Povetkin on Sept. 22 in front of what is expected to be a full house at Wembley Stadium in London.