There was mutual resentment on the set of the show, now named Saturday Night Live
When Chevy Chase returned to host Saturday Night Live he showed up with what his former castmates perceived as a chip on his shoulder. He demanded a return to the Weekend Update news desk, which he had routinely occupied during his tenure on the show. He also castigated writers, criticized other members of the cast, and argued frequently with Chase. During rehearsals in the week leading up to the show, Murray and Chase exchanged numerous barbs. In one Chase described Murray, to his famously pock-marked face, that he looked as if Neil Armstrong could use it for a landing site (Armstrong had by then landed on the moon among its many craters). Murray had already uttered a salty comment regarding Chase’s wife, with whom the comedian was then experiencing marital difficulties. Heavy drug use among the performers exacerbated the tensions throughout the week.
Finally, minutes before the live program was to begin with a Chase monologue, he confronted Murray in John Belushi’s dressing room. The fist fight was brief, though punches were landed by both. Most of them landed on Belushi, who jumped to separate the two, quickly assisted by other cast and crew. Among them was Murray’s brother, Brian Doyle-Murray. Fellow cast member Laraine Newman later called the scuffle, “…very sad and painful and awful”. Chase left field of conflict to start the week’s program before an audience clueless as to what had just occurred. Years later both combatants acknowledged their roles in the altercation and claimed that although they are not close (Murray is famously reclusively) they are on friendly terms, befitting two stars of Caddyshack.