Deontay Wilder is expected to reject a fight with Anthony Joshua in favour of a rematch with Luis Ortiz.
That is the view of Joshua's promoter Eddie Hearn who has long been negotiating with the American.
Wilder knocked out Dominic Breazeale in the first round on Saturday night to retain his heavyweight world title.
He later said he was committed to making the fight with fellow champion Joshua.
But Hearn told Sports Illustrated that Wilder is close to making a deal for a second fight with Ortiz.
The Cuban pushed Wilder all the way last year before he was stopped in the 10th round.
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He has since notched three victories over average opponents and recently rejected the chance to face Joshua on June 1.
Ortiz was Joshua's first choice opponent to replace Jarrell Miller who failed three drug tests, but a deal could not be agreed.
After his victory, Wilder said of the Joshua unification: "It will happen, I'm going to cut to the chase. The heavyweight division is lit right now and it's our obligation to make it happen.
"The next time it comes around to discussing it, I think the deal will get done.
"People have to have patience but it will happen, I promise you that."
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Hearn had hoped to agree terms with Wilder for the unification clash later this year but those hopes appear to have been dashed.
He said on Saturday: "The fight with AJ and Wilder is the biggest fight in the sport and all being well in two weeks' time it must happen next - no excuses, this is the fight that will change the sport globally.
“It's a legacy fight and AJ wants it so bad. Two big, fast, dangerous and fearless world heavyweight world champions that can turn the lights out with a blink of the eye - it's a must.
"First things first, taking care of business on his American debut on June 1 and send a message straight back."
