Mayweather also has a very good chin and has never been down. Which is even more trouble for Pacquiao if he catches him
I still think he went down vs Judah, but that's just me.

Before Pac faced Hatton people talked about certain weaknesses/flaws that would make Hatton pay and that's what happened. As for Mayweather, what can we say that will make him lose if he has not shown any clear weakness/flaw?

Let's see how Mayweather performs vs Marquez coming July and then we'll talk about Mayweather being rusty or not. Remember, JMM has given Pac his biggest challenges ending in two questionable decisions. So if Mayweather beats JMM in a convincing fashion then it will serve as a statement. Pretty much like having them say this to each other "Look at how easily I bet Hatton and you took you more rounds than me to beat him?...Look how I dominated JMM and you got gift decisions TWICE?".
I am going to Vegas to watch this fight.