And no MrBig I'm not saying they weren't great, they were the best of their age and that is as great as you could get!

But that doesn't afford them superhuman status. You said it yourself, you can only judge them against the criteria of their own era. That criteria is different now.

And I've no doubt there was reasons behind Ali's struggles (although struggling against Fraizer and Norton 3 times each is hard to justify) but 2 things are obvious..

He was not a DOMINANT champion like Tyson, LEwis and the Klitschko's were. He was more like a Holyfield. A great boxer who would always be at the top but who could never hold on to a title for long.

And if you excuse Ali's struggles and losses then you have to be prepared to do the same for Klitschko too. The GASSING against Puritty, the HEADBUTT against Sanders, the HYPERGLYCAEMIA against Brewster (whatever the cause). Just as we know the issues with Holyfield too.