A deal has been reached for light heavyweight contender Andrzej Fonfara to face former middleweight titleholder Julio Cesar Chavez Jr. on April 18 at an undisclosed weight and at a site to be determined. However, Bob Arum, Chavez’s promoter in arbitration, says the Mexican star owes him one more fight

The fight was confirmed on Monday by Fonfara’s promoter Leon Margules, of Warriors Boxing, and Sam Watson, right-hand man to the fighters’ mutual adviser Al Haymon.

Chavez Jr. (48-1-1, 32 knockouts), THE RING’s No. 9-rated super middleweight, announced the news on his Twitter account.

“Done deal,” read Chavez’s tweet. “I’m fighting Andrzej Fonfara on April 18.”

“The fight has been agreed to. Chavez and Fonfara are going to fight,” Margules told RingTV.com. “I can’t disclose the weight class yet, because that’s confidential. April 18 is the date, but I don’t know where, and I don’t know the network.

“(But) anytime you have the opportunity to fight a great name and to be in a competitive fight that a lot of people are going to watch, it’s great for your fighter. We were offered the fight, and we took it. Obviously, I was offered the fight by Chavez’s people. I don’t want to mention who offered it. It was a fight that we were able to agree on.”

The son of Hall-of-Famer and three-division champion, Julio Cesar Chavez, is coming off a 168-pound unanimous decision over Bryan Vera in March 2014, having won their previous bout by controversial unanimous decision in September 2013. Chavez-Vera I happened in California at a 173-pound catchweight because Chavez was not able to make the originally contracted limit.

Prior to facing Vera, Chavez was dethroned as WBC middleweight titleholder following a unanimous decision loss to Sergio Martinez, who was floored in the final round of their fight in September 2012.

Fonfara (26-3, 15 KOs) is coming off November’s unanimous decision over Doudou Ngumbu at Chicago’s UIC Pavillion, where the 27-year-old is immensely popular. Fonfara had brought a run of 15 straight victories, 12 by knockout, into his previous fight, a unanimous-decision loss to RING champion Adonis Stevenson, whom Fonfara dropped in the ninth. Prior to that, Fonfara had last suffered defeat against Derrick Findley by second round stoppage in July 2008.

Chavez’s November signing with Haymon indicated his desire to separate from career-long promoter Top Rank Promotions, given that CEO Bob Arum is not usually known to do business with Haymon. Top Rank filed suit against Chavez in August alleging that the boxer owes the company one more fight and that he has until April 6, 2016 to grant it.

Asked if Chavez could legally fight Fonfara, Arum said, “No.”

“He can Tweet all that he wants that he’s fighting this guy or that guy,” said Arum. “We have a contract with him. Let him fight one more fight for us, and then, we can say goodbye.”

Neither Top Rank attorney Dan Petrocelli of the Los Angeles-based O’Melveny and Myers law firm, nor Chavez’s attorney, Howard Weitzman, of the Santa Monica-based Kinsella Weitzman law firm, could be reached for an immediate comment.

“Top Rank has exclusive rights to another Chavez fight,” said Petrocelli to RingTV.com in November. “The matter is pending in court and anyone, including Mr. Haymon, who disregards this runs the risk of serious liability for interfering with Top Rank’s rights.”

Weitzman contended that the Top Rank contract expired “at the end of September, 2014.”

“The issue is really narrow with respect to Top Rank and Julio and that issue is that we believe that the contract has expired and Bob Arum believes that he has one fight left on the contract,” said Weitzman also on November. “If we can’t settle it and it doesn’t appear that we’re heading that way, because they’ve filed a lawsuit, then some judge or jury will make that decision. Has the contract expired or has it not?”

Arum said he would be willing to work with Haymon “if the fight could be done the way that we’ve done all of” Chavez’s fights, adding, “Whoever he wants to advise him, that’s beyond our control and we couldn’t care less.”

“We have done all of his fights for all of his career,” said Arum, “and we would promote those fights in the same manner.”

Would Haymon’s role as adviser to Chavez, in itself, violate a Top Rank promotion of his next fight?

“I can’t answer that without knowing what it is that he has allegedly signed and what the terms are and whether the agreement in any way violates Top Rank’s rights. So Mr. Haymon, if it’s true that he signed Chavez, then we’re not aware of any official confirmation other than what has been reported in the press,” said Petrocelli.

“But it would raise some very serious issues as I said because Top Rank has exclusive rights to at least one more fight. What would Al Haymon’s role be? Why does he have anything to do with Chavez? Fighters can have all kinds of advisers but the way that it’s being presented in the media is that since he has signed with Al Haymon, he’s not available to Top Rank anymore. So that’s a violation of Top Rank’s rights.”

Weitzman also contended that the ongoing litigation should not keep Chavez out of action.

“We believe that we’re entitled to go out and to fight, regardless, and that the case will take care of itself. I believe that he can book a fight and participate in the fightÔǪthere is a lawsuit that’s been filed that is asking a judge to find that Top Rank has one more fight. We’ve answered in counter claim that the contract has expired,” said Weitzman.

“But at the end of the day, this is about money. I mean, Bob Arum doesn’t own Julio Cesar Chavez Jr., so it’s really about the moneyÔǪso because it’s only about the money, I believe that Julio Cesar Chavez is entitled to fight, and then, like most litigations, we’ll have a dispute that will be decided with respect to if anybody gets money and, if so, then, how much?”

Margules got the last word.

“Chavez has accepted the fight, Fonfara has accepted the fight,” said Margules. “It’s a great fight between two good fighters, and it’s the continuation of some great fights that are being made this year.”