By Miguel Rivera

World Boxing Council President Mauricio Sulaiman has cautioned his middleweight champion, Gennady Golovkin (38-0-1, 34 KOs), that if he doesn't fight Canelo Alvarez in a rematch in September - then he will have to make mandatory defense against WBC interim-champion Jermall Charlo.

Golovkin and Canelo had been negotiating the terms of a rematch for the last few weeks - with the target date of September 15th in Las Vegas.

In the last few days, their negotiations have fallen apart over a tense dispute with respect to the financial split. Canelo is holding strong to a 65-35 split, while Golovkin wants an even 50-50 split. 

If the rematch doesn't happen, Golovkin - who holds the IBF, WBA, WBC, IBO world titles - will have to make a mandatory defense against Sergiy Derevyanechenko.

But the WBC believes Charlo is the mandatory fight that needs to happen. Charlo became the mandatory challenger in July 2017, when he won a final eliminator over Sebastian Heiland.

"Golovkin has all our support, but if the fight is not done, he will have to go with Charlo, because the entire history is clear as it is, so we are recommending to him to do what is best for him, because he wants to do the rematch [with Canelo], he wants to earn the money that he will generate there, and he wants that visibility that he has always wanted around the world," Sulaiman told ESPN Deportes.

"He has sacrificed so much for so many years to get to this point and now for something that is not so important [like the financial split] is putting him at risk. It would be strange to me if that fight [with Canelo] is not done."

Because of the financial issues, Canelo's handlers are already starting negotiations with other top middleweights, like WBO world champion Billy Joe Saunders of the UK.