Turned the tide of fights. Julian Jackson caught a headbutt late in the first fight he had against McClellan, and it seemed to completely turn the tide of a fight that Jackson was coming on very strongly in. Roldan vs. Hagler, with the thumb?
In the first Greb Tunney fight, Greb somehow opened up a four inch gash over Tunneys brow which severed an artery.
It was accidental, but that headbutt rocked Torres and left him wide open for that huge knockout punch.
Benn-McClellan... I still think the hedbutt from Benn damaged Gerald tremendously and after it occurred I think the fight was genuinely over for the American...