The Australian, Joel Brunker, has fought twenty-seven men so far and he’s beaten every single one of them. Brunker’s last victory was in Atlantic City, USA, over the respected Mike Oliver whom Brunker beat comfortably, as indicated by the unanimous decision. In support of Brunker’s unblemished professional record is his supreme level of fitness and conditioning which is a result of his sheer hard work and dedication to being the best that he can possibly be. The IBF ranks Brunker at number 3 in the world.
In terms of boxing, what can be said of Carl Froch? He’s not just ‘as tough as they come’, he’s tougher. He’s the epitome of resolve. He’s a vicious and hurtful puncher. He’s hugely experienced at the highest levels of boxing. He’s a very serious risk to any fighter in the world at any given moment in a fight, regardless of whether it’s the first round or the twelfth. He’s a world champion boxer. How could one argue over these statements when the world witnesses the aforementioned whenever Carl steps into a ring? It’s fact, Carl Froch is a resilient, hard-hitting world champion. 
Credit where credit’s due, most fighters in Nathan Cleverly’s position would avoid a showdown with such a fierce-punching, and unbeaten, rival. There may well be unanswered questions over Sergey Kovalev’s endurance, but why worry about endurance when concussive power in both hands negates the need for such a trait? And who’s to say that the Sergey couldn’t destroy opponents all night long if necessary?