Guinn informed Hearn via a doctor’s note that he could no longer participate in the contest, which was due to be a warm-up for Whyte prior to a massive British heavyweight title battle with Olympic champion Anthony Joshua.
Undefeated Londoner Whyte, 27, made his disappointment at losing his opponent at short notice clear via social media, although Hearn has now turned to 40 year-old Minto in his bid to find a suitable replacement.
Minto has won his last two low-key affairs on the back of New Zealand losses to Israel Adesanya and Joe Parker, although throughout his career, the Pennsylvanian has usually been pegged back when stepping up towards the top level and has suffered defeats to Chris Arreola and ex-200lb champion Marco Huck during his cruiserweight days.
The contest has been sanctioned for the WBC’s International title, meaning Whyte will be given a timely boost by the World Boxing Council if victorious before taking on their number two contender in Joshua.
Joshua himself fights on the bill against rugged Scot Gary Cornish in a bid to claim the vacant Commonwealth strap previously held by Australian puncher Lucas ‘Big Daddy’ Browne.
Tickets for Heavy Duty featuring Anthony Joshua and Dillian Whyte can be purchased here