Normally the ref will spot it and either rule no KD or call it either a DQ loss or a No Contest. Tough to get away with it...I can think of a couple where someone was caught with a headbutt on the way down from a shot, like Tyson-Carl Williams, but not one where the winner got away with openly nutting his opponent down and out.
Robin Reid knocked some dude out with a headbutt a few years ago. He was sat on the floor complaining about the butt and the ref counted him out.
What a stupid thread. who cares, when your in the ring, you use your fists. headbutt is street fighting manuever. we are prizefighters, not street fighters.
A few years ago my friend Albert Williams was fighting Ed Mahone in Las Vegas, the fight was close and both were pretty tired. However Ed clshed with Albert Temple against the ropes and Al sunk to the canvas, the referee counted and Al couldn't continue, It was then declared a Tech Draw... Thats as close as it gets.....
moorer was taking jirov apart. then a lone headbutt made him totally inconherent. and somthing we dont like to talk about. the Benn-McClellen fight was an even fight until a right hand by benn skimmed past geralds chin and nigels head clashed into his temple....peopel belive it was the headbutt that caused the damage...but a few 100 punches to the dome didnt help
I gotta admit, when i was going through my mind to think of any examples, the first fights i went by was Holyfield's career.
Evander Holyfield knocked Lou Savarese down with a headbutt. I think Edison Miranda knocked Sherwin Davis down with a headbutt, or a clash of heads.
I always questioned That Marvin Hagler might have used his head on that final blow when he knocked out Tommy Hearns for an extra hit. (Tho not on purpose) Check it out.