Povetkin, the 2004 Olympic champion and former WBA World Champion, was due to challenge WBC World Champion Deontay Wilder, in Russia, on the same day as Parker faces Carlos Takam this week. 

That bout is now off.

Takam’s only knockout loss is at the hands of Povetkin two years ago.

Meldonium is the same drug for which tennis star Maria Sharapova recently tested positive. It was approved to be added to the banned substance list by the World Anti-Doping Agency in September, and the ban went into effect Jan. 1.

Meldonium is used to increase blood flow and carry more oxygen to muscles, thereby enhancing stamina, a trait boxers would want in a long fight.

In a press conference in Auckland last week, Takam’s promoter Christian Cherchi said his boxer’s 10^th round knockout lost to Povetkin was because “he gassed”.