In a hotel suite in Chelsea, the last of the heavyweight giants from boxing’s golden age is in full flow. In his booming preacher’s voice, George Foreman is opining on the legends of Muhammad Ali and Joe Frazier, the young upstarts Tyson Fury and Anthony Joshua, and even revealing that he is siding with Donald Trump in the imminent US election. The man who brought us the lean, mean grilling machine even has a new invention in mind, shoes that can make the older generation “get up and walk”.

Foreman is unstoppable, just as he was while crushing opponents as the king of the division at the age of 24, and still looks like he could cause a few ripples there right now. He still weighs in at 18st 4lb, which was his fighting weight as world champion, and while his face is furrowed by wrinkles, he still moves – and talks – like a man half his 67 years.