Dillian Whyte is now the frontrunner to fill the vacancy for April 13 when a return to Wembley Stadium is already booked for Joshua, who must first defend his world heavyweight titles against Alexander Povetkin on September 22 live on Sky Sports Box Office.
An undisputed title bout between Joshua and Wilder remains the “fight that world boxing needs” according to Hearn, but he claims that negotiations with the WBC champion are at a standstill.
Asked if he had heard from Shelly Finkel, Wilder’s representative, Hearn told Sky Sports: “Absolutely nothing at all.
“If there’s even a chance that an undisputed title fight could happen in April, you’ve got to at least talk about it.
“Maybe they don’t use emails – maybe Shelly uses carrier pigeons or smoke signals. I’m going to strap a note to a pigeon’s leg and send it to New York,” Hearn joked.
Wilder, who holds the only belt outside of Joshua’s grasp, is planning to defend his WBC title against former heavyweight champion Tyson Fury next.
“It’s not a case of saying they’re concentrating on Fury,” Hearn said. “It’s the promoters’ job to plan ahead.
“It’s frustrating because there’s limited time to make the fight. People must be realising that they don’t want the fight because, if they did, why haven’t they replied?”
As a result Whyte, whose only defeat was against bitter rival Joshua in December 2015, is the lead contender to agree a rematch for April at Wembley.
“At the moment, yes,” explained Hearn who is first negotiating to pit Whyte against Dereck Chisora for the second time.
“He is first going to fight in December. We are negotiating, talking for December 22 at The O2.
“Making a fight when the fighters don’t particularly like each other is very difficult. But generally people are bright enough to swallow their pride, and get it done. There’s a good chance.”
Whyte and Chisora both shone in exciting victories on the same card in July, against Joseph Parker and Carlos Takam respectively. Whyte beat Chisora by split decision in December 2016 when they first fought.
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