Dmitry Bivol and Artur Beterbiev have been backed as the only men capable of troubling Saul 'Canelo' Alvarez.
It has been widely reported that Canelo Alvarez has been given the green-light by the WBC to step up to cruiserweight to challenge Ilunga Makabu for the vacant title.
Bivol, 31, and Beterbiev, 36, are both still undefeated in their respective boxing careers so far, boasting a combined record of 36 wins and 28 knockouts between them.
And George Groves believes the light heavyweight duo are the only ones who can genuinely give Alvarez a good run for their money if he does indeed make the move up from super-middleweight as is anticipated in the new year.
Retired Groves, 33, told Sky Sports: "You need power to get Canelo's respect, but I don't think that will be enough.
"Canelo is so clever, he's so good, and I can't see anybody troubling him, especially not at super-middleweight.
"David Benavidez lingers between super-middleweight and light-heavyweight. He's a very well schooled fighter, but he must be more disciplined. You'll need plenty of discipline for the Canelo fight.
"The top light-heavyweights like Dmitry Bivol and Artur Beterbiev would provide a genuine test for Canelo.
"He's talking about fighting Ilunga Makabu at cruiserweight and Canelo probably beats him all day long, but all of a sudden you're in a different sort of fight.
"[Oleksandr] Usyk would be far too big for him, but I doubt Usyk would ever come back down to cruiserweight now."
Canelo's masterful technical skills has Dave Coldwell - who famously trained Tony Bellew for his knockout win over Makabu in May 2016 - respectfully disagreeing with Groves as he feels he is a better technician than both of those men.
However, he did suggest that Bivol has the best chance of beating Canelo out of the two, but reckons the Mexican would still find a way to win somehow.
He added: "Size and weight are the greatest threat to Canelo. If he steps up to cruiserweight, they are big opponents up there.
"He could fight Ilunga Makabu next and people are suggesting it's an easy opponent for Canelo, but he's not. Makabu can punch. I know he's not the biggest of guys, but he's still pretty big, he hits hard, and he's tough.
"But if Canelo goes to light-heavyweight, I believe he can beat Artur Beterbiev, I really do.
"Dmitry Bivol is somebody that might prove quite awkward for him. Bivol is a sharp shooter, he's got good legs, which could be a challenge for Canelo.
"Those guys at light-heavyweight are a threat, but I still think Canelo can find a way to win."
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