One of boxing’s more interesting cards in recent memory occurs Saturday in Saudi Arabia when Queensberry Promotions and Matchroom Boxing, two of the sport’s biggest promoters, each put forth five fighters to compete in a showdown between two promotional heavyweights.

Queensberry is headed by Frank Warren and promotes fighters such as Tyson Fury and Joseph Parker. Matchroom Boxing is led by Eddie Hearn and promotes fighters including Anthony Joshua, Katie Taylor and Edgar Berlanga.

Hearn and Warren have had their differences in the past but after working together on previous Saudi-sponsored cards. They decided to come together and settle their differences with an in-ring showdown between five of each promotion’s best fighters.

“The best sport stems from the greatest rivalries. And on June 1, I am confident Matchroom will reign supreme over Queensberry,” Hearn said in a press release. “… With the brilliant Dmitry Bivol challenging for the undisputed light-heavyweight championship, this is without doubt one of the best boxing cards of all-time.”

The card is headlined by a heavyweight showdown between former champion Deontay Wilder and top contender Zhilei Zhang.

The undercard features light heavyweight world champion Dmitry Bivol defending his WBA belt against Malik Zinad.