Would Rousey/Holm/Tate beat you in a fight?
 

Not necessarily you, but how about an average sized male with no formal martial arts training?



I'm 6'0, 190 pounds and I've taken a handful of BJJ and MT classes, just enough to know the basics.

My size/strength/reach still gives me the advantage over a 5'7" 135 pound woman, regardless of their training.



Their blows just won't have the same effect on someone with 50% more size, if they can even land a blow due to my reach advantage. On the ground, if they go for an arm bar or choke hold, they won't have the strength to execute it.



Am I underestimating the skill of a professionally trained female fighter?

I am impressed with the skills the modern top level MMA women. That being said I fully believe that I could beat any woman in a fight.



The average man however I don't think they would stand much of a chance against most trained woman fighters.

^ pretty much what he said. It's easy to underestimate a smaller/weaker opponent; skill goes a looooong way in a fight.