Callum Johnson 21-1 (14) has been forced out of his world title tilt against WBO light heavyweight champion Joe Smith Jr 27-3 (21) after contracting Covid-19.
The bout was scheduled to take place at the Turning Stone Resort & Casino in Verona, New York on January 15.
“It’s a real great shame for Callum,” promoter Frank Warren told BBC Sport. “Hopefully we can get him back in, they may want to [reschedule the fight] in late spring. He worked really hard to get the opportunity.”
The hunt is on for a replacement opponent with WBO number one contender Anthony Yarde 22-2 (21) in the box seat to land the fight.
“If Callum doesn’t get his shot then Anthony Yarde is next,” said Warren, who promotes both Johnson and Yarde.
“I’d love to do Joe Smith v Anthony Yarde in the UK. The WBO say there is a mandatory due and it’s going to be Yarde. He is the number one.
“Anthony looked so good in his last fight against Lyndon Arthur. We’ve got him down to fight sometime in March anyway. Fingers crossed.
“We’ll see what happens next week with Smith and how he comes through. Then go from there.
“I want to keep Anthony busy. We want to get the world title shot for him. The experience he’s gained since [fighting] Sergey Kovalev stands him in good stead. He really gives Smith so many problems.”
If Yarde doesn’t get the call up to face Smith, Warren says he is prepared to put in charge in with fellow knockout artist Joshua Buatsi 15-0 (13).
That bout would be a huge domestic showdown that promises fireworks. Another fight that Warren wants to make is Conor Benn vs David Avanesyan. These fights would require Warren to work with rival promoter Eddie Hearn of Matchroom Boxing.
“We don’t even need a tournament, we’ll make the fight. It’s not a problem for us, let’s do it,” Warren said of the proposed Yarde vs Buatsi bout.
“We’ve been talking about this for years. There was the meeting with Eddie Hearn that never happened. There’s loads of domestic fights to be made.
“I want Zach Parker in with Chris Eubank Jr. Conor Benn is another. I’d love him to fight David Avanesyan.
“That’s a great fight and I think our man wins. I even said put Benn v Avanesyan on DAZN and I’ll pay Avanesyan’s purse. I’ve told Hearn’s people this.