Green’s Dictionary of Slang

knock down and drag out v.

to fight violently.

1834		Caruthers Kentuckian in N.Y. I 189: He’s a bark-well and hold-fast too, he doesn’t honey it up to em and mince his words [...] he knocks down and drags out.
1842		Nichols’ Wkly Arena (NY) 4 June n.p.: The police will try to rush in, and [...] there will be knocking up, knocking down and dragging out.
1856		Life in Boston & N.Y. (Boston, MA) 11 Oct. n.p.: William G. — can drink more r.g., turn more alligators inside out and knock down and drag out more dagos than any other man on the Basin. We’ll bet a hat on him. Hurray for Bill!
1880		Dodge City Times (KS) 6 Nov. 2/4: He had been knocked down, dragged out, left for edead.
1912		J. London Smoke Bellew (1926) 232: ‘It’s knock down an’ drag out an’ plow through!’ Shorty yelled in his partner’s ear.
1914		Day Book (Chicago) 10 Nov. 28/1: Poor old Vice is about to be knocked down and dragged out again in Chicago.