Who punches harder Mayweather or Marquez?

[El Kabong]

Mayweather's power comes from speed and timing, JMM's power is strength and timing...little different, but at the weight I know Floyd's is more tested.

[OumaFan]

I don't think there's much difference although its obviously still an unknown how he'll carry it up, I think even against a somewhat past it Casamayor Floyd would have had a hard time hurting him with one punch as much as JMM did. In fact I'd go as far to say Marquez has been more of a concussive one punch type at 135 than Floyd was.

[CFH]

Mayweather hits significantly harder than Marquez.