For those who doesn't know McClelland, he was MW WBC champ for 12 months, and his best win was against J. Jackson. The two other defenses he had were against J. Bell and G. Baptiste. Gerald also lost to guys like Dennis Ward and Dennis Milton - both guys outpointed Gerald. At 168 he has only really met Steve Harvey whom very few have ever heard of and Nigel Benn. Benn KOed him in the 10th round. Who would win if they fought?
Kessler UD or possible stoppage late. Mcclellan (there is no d), would always stand that outside chance of stopping anyone, as he hit hard and his body work was lovely. But I think Kessler, who is the better boxer of the two, has the ability to withstand his onslaught over 12.
McClellan in one round, by virtue of him being a fighter of the past, and a "what could have been". No one can withstand that combination.