Green’s Dictionary of Slang

(US black) a fight in which each combatant uses only their head.

a.1909

press cutting in J. Ware Passing Eng. of the Victorian Era 52/2: Stacey appeared to be the more belligerent of the two, insisted on having the quarrel out, and challenged Kline to fight him without fists or weapons. This is the usual manner among Philadelphia negroes to denominate a ‘bucking match’, which is not an infrequent method of settling disputes.