What I have noticed over the years is that the first thing that goes in a boxer is head movement.  This is especially important in an offensive fighter who moves forward.   They get older, they lose the ability to reflexively move their head out of the way of a punch, and they seem to lose the continuous head movement required to keep an opponent confused.   When a fighter tries to get inside, he has to keep his head moving at all times or he's just going to walk right into punches.  A defensive fighter who generally is moving backwards or side to side isn't as reliant on head movement to avoid being hit.  

 

I've also noticed over the years that boxing fans tend to greatly overrate offensive fighters and greatly underrate defensive fighters.  

 

What I have just said may seem obvious to all you boxing aficionados, but I'm just explaining why I am picking Mayweather to win.   Both these guys are getting older, but I think age affects a fighter with Pacquiao's style more than it would affect a fighter with Mayweather's style.   I don't know what would have happened if these guys had fought a few years ago, but right now, I think Mayweather will pick him apart and win easily.  

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