A fight is brewing over the mandatory obligations that are owed by IBF, IBO, WBA, WBC middleweight champion Gennady Golovkin (37-0-1, 33 KOs).

Golovkin was scheduled to defend his titles in a rematch with Canelo Alvarez on May 5th at T-Mobile Arena in Las Vegas.

But last week, Canelo withdrew from the contest. The Mexican star was placed under a temporary suspension by the Nevada State Athletic Commission, because the boxer tested positive for clenbuterol in two separate drug tests taken in February. Canelo must appear at a hearing on April 18.

World Boxing Council President Mauricio Sulaiman has no problem with approving Golovkin to make a voluntary defense against Gary "Spike" O'Sullivan on May 5, and then move forward to a rematch with Canelo in the fall.

"How can you penalize Golovkin when the fight has to happen within a month?" Sulaiman said to the Los Angeles Times. "You have to support your champion. It'd be so unfair to penalize him now when, for reasons out of his control, his fight [with Alvarez] is off. We'll support him and allow him to proceed to Canelo."

But Lou DiBella, the promoter for Golovkin's IBF mandatory challenger, Sergiy Derevyanchenko, is pushing hard for his boxer to get his earned opportunity - and he is fuming at the idea of having his boxer wait until 2019 to fight GGG.

"[A late withdrawal] is not supposed to stop a mandatory from happening," DiBella said to the paper. "I don't understand saying that extenuating circumstances allow something different. Is the extenuating case that he doesn't want to take a risk? That's what it seems like to me."

Based on the IBF rules, says DiBella, Golovkin has to face his boxer this year.

"[Golovkin] has been training for more than a month to fight the toughest guy in the division. What is wrong with switching to another conventional, right-handed fighter who comes forward? How can he not be prepared for Sergiy Derevyanchenko? And our guy is in the gym and ready to fight. So I don't understand any argument against him," DiBella said.

"When a guy is sitting in a mandatory spot, he's not getting paid until he gets that [title] fight. And if Golovkin faces Canelo next, this decision could affect [Derevyanchenko] for 18 months."

According to Sulaiman, there is a conference call scheduled for Tuesday with the IBF and WBA to discuss the situation with Golovkin's mandatory obligations.