Of course he's going to say that, he's an all time great and has supreme confidence of his ability in his prime.
Personally, I don't see it. Putting the "who fought the better competition" nonsense aside, stylistically I just don't see it happening. The only one of that era I would give a great chance of beating prime Mayweather is Tommy Hearns (thats excluding Hagler, because PBF never fought at MW).
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