After three months of verbal sparring and negotiating through the media, the much-hyped heavyweight unification bout between unbeaten champions Anthony Joshua and Deontay Wilder will have to wait until April 2019 at the earliest. 

Wilder (40-0, 39 KOs), the WBC champion, confirmed via a lengthy post on social media early Thursday that he and his team have "bent over backwards" to make the fight a reality for this fall in Joshua's native England. Wilder, who said Joshua was "not a stand up guy," revealed he was willing to accept what he termed "the lowest [financial] offer in boxing history for a unified title bout" just to make it happen.

"We move forward, the future is still bright," Wilder wrote, in closing, before referencing his goal of a 51-0 record, which would best retired pound-for-pound king Floyd Mayweather's unbeaten mark by one fight.

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Along with the September middleweight title rematch between Canelo Alvarez and Gennady Golovkin, the proposed heavyweight title bout, designed to unify all four recognized belts for the first time, would be the biggest fight the sport could make and the most anticipated the division has seen in over 15 years. 

Deciding which fighter is most to blame for the can't-miss fight coming to fruition depends upon which side of this very public soap opera you believe. 

Joshua promoter Eddie Hearn of Matchroom Sport told ESPN on Thursday that Wilder co-manager Shelly Finkel failed to return the contract with his own comments regarding changes in a timely manner. The apparent stalling, according to Hearn, annoyed WBA president Gilberto Mendoza to the point that he ruled Joshua (21-0, 20 KOs) must face mandatory opponent Alexander Povetkin (34-1, 24 KOs) next. 

"We're fighting Povetkin in September and we're looking at multiple venues and dates," said Hearn, who is expected to place the fight in London. "We have a deal with Povetkin agreed to, but it's not signed yet."

Although Hearn said his most recent offer is still valid for 2019 and expressed hope that the fight would come off on April 13 at Wembley Stadium, where Joshua knocked out former champion Wladimir Klitschko in front of 90,000 fans last year, Finkel disputed the majority of Hearn's comments. 

"We're disappointed, but we're not surprised," Finkel told ESPN. "Deontay and I thought about this, that they weren't going to do the fight. We're disappointed. We wasted a lot of time."

Finkel, who said he had the paperwork and saved emails to back everything up, claimed there was never an imposed deadline from Hearn to respond with comments to the latest offer. Hearn, meanwhile, said he emailed Wilder on Tuesday night hoping to get a deal finalized for next April and not this fall.

"I sent a personal email to Deontay and I said to him I'm very disappointed your team did not come back to me with comments on the contract," Hearn said. "We hope we can get this fight over the line and we look forward to receiving a signed contract or comments as soon as possible [for an April fight]."

Hearn said he offered Wilder, 32, a two-fight deal which included $5 million to make a title defense this fall in America on the streaming platform DAZN, which Matchroom Sport recently signed an exclusive deal with, and $15 million to face Joshua next year.

"If you have a so-called manager that received a contract and you want the fight so bad for $15 million and the undisputed title, and you don't read that within 24 hours and have it back within 48 hours, you're doing your fighter a disservice," Hearn said. 

Another issue that came up during negotiations, according to Finkel, was that Hearn's contract provided Joshua, who holds the WBA, WBO and IBF titles,  a rematch clause should he lose but not one for Wilder.

What has made the public negotiation difficult to follow was how often both teams accused the other fighter of not wanting to actually make the fight. Along the way there was plenty of calculated power moves, which included an offer from Hearn to Wilder of $12.5 million to fight in the U.K. (which was later upped to $15 million) and a counter offer from Wilder's camp of a flat fee of $50 million, which included moving the fight to the U.S. and Wilder's team controlling the promotion of the fight. 

Hearn has readily maintained he never believed the $50 million offer to be real or that Wilder's team, which includes co-manager Al Haymon, even had the money. Wilder only complicated matters two weeks ago with a bit of a false flag by going public that he accepted the terms of Hearn's most recent offer to fight this fall in the U.K., even though he had yet to receive a contract. 

In a clear sign that the fight had fallen apart, Hearn took part in a Twitter debate with Showtime Sports president Stephen Espinoza regarding whether Hearn has been publicly truthful about the details of the negotiation. It was an exchange further complicated by the fact that Joshua's exclusive U.S. television deal with Showtime expired in March following his unification win over Joseph Parker, leaving him a free agent.

As Joshua, 28, prepares for a bout with Povetkin, the 38-year-old Russian whose history of performance-enhancing drug use cost him a chance to face Wilder in 2016, it's becoming likely that Wilder will face Dominic Breazeale (19-1, 17 KOs), who was knocked out by Joshua two years ago. The 6-foot-7 Breazeale has history with Wilder dating back to a 2017 melee in the lobby of an Alabama hotel in which Breazeale accused Wilder's brother of punching him.

"It's in the hands of Deontay Wilder," Hearn said. "So every Instagram video he posts saying Joshua doesn't want the fight, shut up. Come back with the comments on the contract and we'll work it out [for April]."