There are some fighters in the past I think would be favored over him, but I was assuming this was meant if another fighter would be favored over him during his time.

I don't think any fighter at 147 or below would be favored over him but that doesn't mean that mayweather couldn't lose because of styles. I always thought that Cotto would have given a lot of trouble to mayweather a few years before they actually fought. A Mosley at 135 could have beaten Floyd too.

Other than that, I can't see anybody who I would give much of a chance to although we know that sometimes people surprise you (maidana for example).