The boxer previously described the blow that ended Daniel Dubois’ IBF title run in July

As ‘Ivan’ and now Russ Anber has told how they had been working on the punch since early 2017 but using the moniker meant that even now, very few in the training camp know what they are referring to.

Russ told Boxing News: “We were in California [in 2017] working on various things on the bag… we worked specifically on this left-hand punch.

“I’m not saying Usyk had never thrown the punch before but we worked together on refining it, ensuring it was thrown from the proper angle and discussing why it’s OK to throw it, and so on.

“As Usyk was hitting it repeatedly, he began to land it harder and harder and he named it ‘Ivan’.

“I always assumed he was referring to someone like Ivan the Terrible and the way he would blast everything in his path.

“Ever since them every fight, every camp, I will say to Uysk, ‘Ivan! Ivan! How’s Ivan? Is Ivan working? Throw Ivan!’

“It has been a code word between us for eight years now.

“On those occasions when I haven’t been in camp, I might call him, ask how camp is going and say, ‘How’s Ivan?’ and Uysk will reply ‘Ivan very good.’

“Even other members in camp had no idea what Uysk and I were on about.”

While Ivan has been classified as a left hook, the trainer sees it slightly differently.

He explained: “Usyk’s a southpaw so I don’t really refer to it as a left hook in the same way I would refer to a left hook from an orthodox fighter.

“Having said that, it’s the kind of punch that can be thrown effectively by a right-hander or a southpaw when facing either a right hander or a southpaw.”