By Keith Idec

Carl Froch is as impressed by Oleksandr Usyk as most boxing experts and fans.

The former super middleweight champion is intrigued, too, by the probability of the unbeaten Ukrainian southpaw moving up to heavyweight. Froch cautioned, however, that the undisputed cruiserweight champion’s handlers should be careful to avoid moving Usyk too fast within that dangerous division.

“I think because of the sheer size of him,” Froch told Sky Sports, “and the fact that he boxed at heavyweight as an amateur, I think he can make that transition very well. But it has to be a steady one. He needs to choose his enemies wisely early on. And then we know he’s looking for big AJ. That may be too ambitious.”

The 6-feet-3 Usyk (16-0, 12 KOs) reiterated after knocking out Tony Bellew on Saturday night in Manchester, England, that he ultimately intends to challenge Joshua for his heavyweight titles. At 6-feet-6 and 245 pounds, the huge, heavy-handed Joshua is significantly bigger and stronger than the 6-feet-3 Bellew (30-3-1, 20 KOs), who weighed in at a high of 213½ pounds for his heavyweight fights.

“You can see [Usyk’s] a big unit,” said Froch, who called the Usyk-Bellew bout from ringside for Sky Sports Box Office. “He’s backed up by a lot of muscle. He can go up comfortably and he’s tall enough as well.”

Usyk’s skill and athleticism should trouble bigger heavyweights, but he’ll give away a significant amount of weight to fighters like Joshua (22-0, 21 KOs).

“He is a serious threat to the heavyweight division,” Froch said. “You can say that. I would just like to say that Tony Bellew really put up a top performance, probably one of the career-best performances, but he came up against a fantastic Usyk [Saturday night].

“What a way to end his career. What a shame, but he’s got a lot to be proud of. And we’ve really found someone in Oleksandr Usyk that is very, very special. We need to acknowledge that.”

Usyk was behind on two scorecards when he blasted Bellew with a left hand that left the brave Brit flat on his back in the eighth round (68-65, 67-66, 67-67). Liverpool’s Bellew attempted to get up, but referee Terry O’Connor stopped their scheduled 12-round encounter exactly two minutes into the eighth round, with Bellew on his knees.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.