Knife for sure. If it were knife vs. bat in a fight, the person with the bat only really has 1 swing to make something happen. If that swing isn't dead on, he is getting chopped up. Not to mention once the person with the knife is in close, the bat is essentially useless.
Sig Credit: M.C
Miesha Tate - Urijah Faber - Dustin Poirier - Frankie Edgar - Claudia Gadelha - Demian Maia - Jessica Eye