Following the release of four studio albums, the band finally forged an identifiable sound featuring the twin guitars of Scott Gorham and Brian Robertson.

[2] The track "Suicide" was originally performed by Thin Lizzy when guitarist Eric Bell was still in the band, including on a BBC broadcast recorded in July 1973.

[5] Stephen Thomas Erlewine of AllMusic described Fighting as a "tense, coiled, vicious rock & roll album", with which Thin Lizzy began their classic era.

Highlighting Gorham and Robertson's twin-guitar interplay, he described this line-up as "vital and visceral", and added that Lynott had made a leap forward as a songwriter, "fully flourishing as a rock & roll poet".

[6] In his Collector's Guide to Heavy Metal Martin Popoff called Fighting a "soulful, stirring hard rock classic", where "Robertson and Gorham's fluid guitar harmonies become an integral part of the Lizzy sound, woven in the very fabric of the arrangements" and "the tales of outlaws and outcasts" reach "a fairly grandiose, history-encompassing, tragic scale.