The opportunity (read money) on Dec. 23 in Saudi Arabia was apparently too vast for British promoters Eddie Hearn and Frank Warren to let their bad blood get in the way of an unprecedented collaboration.

Matchroom’s Hearn and Queensberry’s Warren will be involved on an ambitious fight card to take place in the Saudi Arabian capital of Riyadh, two days before Christmas, and which will feature Anthony Joshua against Otto Wallin and Deontay Wilder in a separate fight against Joseph Parker.

The card also includes the return of light heavyweight titlist Dmitry Bivol against Lyndon Arthur, Daniel Dubois against disgraced contender Jarrell Miller, as well as cruiserweight titlist Jai Opetaia and heavyweight contender Filip Hrgovic.

The announcement of that card follows in the wake of the ballyhooed heavyweight “crossover” bout between Tyson Fury and Francis Ngannou last month in Riyadh. Like that event, the Dec. 23rd card is organized and funded by Turki Alalshikh of the General Entertainment Authority of Saudi Arabia. The outfit is also responsible for the upcoming undisputed heavyweight championship between Fury and unified champion Oleksandr Usyk on Feb. 17 in Riyadh.

And, according to Hearn, it was Alalshikh who managed to bring two power brokers who have butted heads for more than a decade. Hearn and Warren have long disparaged each other through the press, much to the titillation of the tabloid public.

In a recent interview, Hearn acknowledged that there was a clear directive from Saudi Arabia to make sure personal animus did not get in the way of conducting business with Warren.

“It’s taken his Excellency to bring that together,” Hearn told iFL TV. “And it was pretty much strict instructions: ‘I don’t care if you two get on. This is what I want, Dec. 23, go and make it happen.’ Like I said, it was such a huge opportunity for AJ, for Dmitry Bivol, for Jai Opetaia, we’d be Muppets if we let that history get in the way of opportunities for our fighters.

“AJ was desperate to fight three times this year. We’ve been able to deliver it. We know what the future holds. We know they want to do the Wilder fight. We know they want to do [light heavyweight undisputed championship] Bivol-Beterbiev. We know they want to do big fights all around the clock. It was important for us to build those relationships. I can’t wait for December 23rd."

Hearn said he and Warren had a brief meeting before the press conference in London on Wednesday—but he denied that there was any unwanted tension.

“It was like, look, rivalry aside, let’s not muck up this opportunity,” Hearn said. “No [it was not awkward] not at all. I think that deep down we’re rivals. That’s been good for the sport because we’re so competitive, we all want to deliver the best shows. When you get an opportunity like this to do something different and to really break down the barriers of the sports, you guys, the fans, you want promoters to work together.

“When this happens, you see all the different fighters on the card. And it’s not just me and Frank. It’s [Wilder manager] Shelly Finke, it’s [Miller promoter] Dmitry Salita, it’s [Hrgovic promoter] Wasserman, it’s all these other promoters that have been part of bringing these fights together in quick time and I think that’s the most impressive part.”

Sean Nam is the author of .