The 48-year-old former super-middleweight world champion was ringside as 28-year-old Stevenson outclassed Lopez over 12 one-sided rounds at Madison Square Garden to claim the WBO 140lb title.
After being crowned a four-weight world champion, Stevenson called out Benn, who entered the ring to confront him. Froch, speaking on SunSport’s No Glove Lost, has now urged caution.
Carl said: “I just watched Teofimo Lopez and Shakur Stevenson. If I’m managing Conor Benn, I wouldn’t want to put him in there with them.
“And I called him a ‘novice’ a couple of weeks ago, which I probably shouldn’t have done because he’s not a novice, but in my eyes, when you’ve not won an English, British, Commonwealth, European title, you’re still building.
“And there’s nothing to say that he can’t go in with some of these top boys and beat them, but there’s nothing that to suggest that he definitely does. So I can’t go out on a limb and say, ‘Yeah, he’ll win a world title in his next fight’. Conor Benn, which makes a mockery of the rankings.”
Benn is currently ranked No1 in the WBC’s welterweight standings despite not having fought in the division for more than three years.
Benn, who fought two middleweight contests against Chris Eubank Jr, 36 – losing in April before winning a November rematch – is expected to be in Las Vegas to watch and potentially call out the winner.
Former undisputed super-lightweight champion Josh Taylor, 35, echoed Carl’s caution.
Josh said about Conor: “He’s never won a domestic title but unfortunately in this business, it’s like, what makes money makes sense. It’s a big massive commercial fight.
“Obviously Conor Benn is a big name in British boxing now, world boxing after the two Eubank fights. So the promoters will be rubbing their hands together, that’s a big, big money fight.”
Josh added: “It can be a little bit of a match because Conor’s big and strong and athletic, size wise, he’s got a chance. But I think Shakur schools him all day. But size-wise and strength-wise and going for a fight, that might take a point in the fight. But I don’t think Conor can outbox him at all, no. I think that’s quite a straightforward fight for Shakur, to be honest.”