Eddie Hearn believes Katie Taylor could fight Amanda Serrano at a packed Madison Square Garden.
And the promoter wants to make the fight happen next year in New York but he still thinks it will be a battle to get Serrano to sign for it.
Undisputed women's lightweight champion Taylor, 35, has been constantly linked with facing the multi-weight world title holder over the last number of years.
And Hearn has big plans for it if he can ever get the Puerto Rican puncher, who has held titles in seven divisions and is currently a unified featherweight champion, to agree to it.
He said: “The Amanda Serrano fight is a must-make fight.
“That's the biggest fight in women's boxing by a country mile.
“That's a fight that could headline Madison Square Garden - but we've got to get it over the f***ing line. And it's so difficult to do.
“And to be fair to Amanda Serrano, her value has increased significantly since we first negotiated that fight.
“It's a bit like when we were talking about doing AJ (Anthony Joshua) against Tyson Fury initially.
“This is a fight that, in my opinion, was a 70/30 split.
“But Fury goes over, beats Deontay Wilder, really, in the first fight, knocks him out in the second fight, so we turn around and go, 'Fair enough - it's 50/50!'
“And I don't think we're there yet with Serrano but we were at a point where it was an 80/20, 70/30 split and the gap is now closing because of what Serrano has achieved. You have to give her the credit for that.
"It's not like Katie is going, 'I want 70 per cent!' Or, 'She's not worth that!' Katie don't work that way. But I still want to be sure that she gets a record payday for that fight.
“She's just the easiest fighter to represent. She'll go back to Bray, she'll have a couple of weeks and then she'll go back to America and she'll just be saying, 'When's my next fight? December?'
“And I see her having one more after this, if she wins, and then we must make Serrano, March or April.”
Taylor defends her titles against American Jennifer Han this weekend in Leeds on the undercard of Josh Warrington's featherweight clash with Mauricio Lara at the home of rugby league side Leeds Rhinos.
Then Hearn plans to have her out in action again in December before trying to sort the Serrano date.
He is considering undisputed welterweight champion Jessica McCaskill or former amateur foe Estelle Mossely for the date before Christmas.
He added: “It could be McCaskill, we've got about three mandatories. I also like the Estelle Mossely fight - the gold medalist from Rio, I've reached out to her as well.”
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