Backstage at the press conference for the fight on Monday (15 January), Ngannou told The Independent and a select group of publications: “If I catch him, then he’s going to sleep. Remember, this is the heavyweight division and everyone is quite strong. You should keep your chin away.

“Don’t go there and sleep [underestimate an opponent] and say: ‘Oh, he’s not the hardest puncher.’ If you put your chin in the right position and get hit, even by the lightest fighters, then you might wake up in the white room. So, you better keep your chin away and fight smart.

“It is not chin-testing, it is a combat sport. I’m the hardest puncher, but I was in a 10-round fight and couldn’t knock out Tyson Fury, I couldn’t connect. [But] you can knock someone out if you can touch them.”

Joshua, 34, last fought in December, also in Riyadh, stopping Otto Wallin after five rounds to secure his third win in as many fights in 2023.

The former two-time heavyweight champion was expected to compete in an IBF title eliminator next, before the surprise announcement of his clash with Ngannou.

Fury’s WBC title was not on the line against Ngannou, but the Briton will defend it against unified champion Oleksandr Usyk on 17 February, as the Ukrainian puts his belts on the line, too. The winner of that bout in Riyadh will become the first undisputed heavyweight champion since 2000, and the victor of Joshua vs Ngannou may yet be next in line for Fury or Usyk.