Oleksandr Usyk should fight Deontay Wilder before retirement, with David Haye dubbing a bout as "the only box left to tick".
The Ukrainian returns against Dutch kickboxer Rico Verhoeven on Saturday, live on DAZN Pay-Per-View and Ultimate Tier.
It comes after the unified champion made vocal attempts to secure a fight with former WBC title holder Wilder late last year.
For onetime two-weight kingpin Haye, a bout between the two would complete a glittering career for the pound-for-pound star.
"Fight this kickboxer, then Deontay Wilder," he told Boxing Scene. "Because then, on paper, he's beaten every man of the era.
"Usyk's fought every dominant champion from his era and reigned supreme, remained unbeaten. That's the only box left to tick.
"He's given the boxing fans everything, the boxing fraternity and the hardcore purists fight after fight. He's fought the very best.
"[He] beat them all twice. I’m not sure what more he needs to prove. If anyone deserves to fight whoever they want, he's that guy."
This is far from the first time somebody has suggested that Oleksandr Usyk should take Deontay Wilder for a trip around the ring.
Indeed, the unified champion himself spent several months around the turn of the year repeating that it was the American he wanted.
Having turned his eventual attention to Rico Verhoeven, Usyk's future roadmap does not seem to include a bout with the veteran.
But with any likely bout against Daniel Dubois due to wait until his rematch with Fabio Wardley is completed, he may yet change course.
Wilder is reportedly in the mix for his own second dance with Derek Chisora. But there remains plenty of variables in play for this one.
Oleksandr Usyk puts his unbeaten record on the line against Rico Verhoeven on Saturday, May 23, in front of the Egyptian pyramids, live and exclusive on DAZN. Buy as a one-off PPV or included, along with Zayas vs. Ennis (June 27) PPV, with a DAZN Ultimate Tier subscription.