The IBF stripped Gennady Golovkin of his middleweight world title Wednesday, according to Yahoo Sports, which has obtained a copy of the ruling.

Golovkin had a hearing late last month over not agreeing to a mandatory fight. He refused to make a deal to defend against Sergiy Derevyanchenko, the organization's top challenger. He would have had until Aug. 3 to prepare for the fight, but Golovkin never agreed.

Yahoo Sports notes the IBF said in a statement that Golovkin fighting "an unsanctioned contest" against Vanes Martirosyan was the primary driving force in the decision to vacate the title. Golovkin fought Martirosyan last month and won with a second-round knockout fairly easily.

The IBF previously said it would invoke its rule 5.H if Golovkin goes through with the fight against Martirosyan, which states, "If a champion participates in an unsanctioned contest within his prescribed weight limit, the title will be declared vacant whether the champion wins or loses the bout. The championships committee, with the approval of the (IBF) president, will then establish a new champion in that division in accordance with the procedures established and prescribed in these rules," according to ESPN.

One of the main reasons Golovkin fought Martirosyan in the first place was because Canelo Alvarez tested positive for a banned substance and was suspended six months. Alvarez and Golovkin were set for a May 5 rematch after they previously fought to a draw, but the rematch was canceled, which led to Golovkin fighting Martirosyan.

Golovkin has a 38-0 record with 34 knockouts.