You go back to 1958 when the Dodgers moved west, and I would bet without going to the Dodgers baseball reference page, few here could name their starting rotation, let alone the guys in the bullpen. And the same would be true of most of the pitching staffs going back, say, 15-25 years or more. For the record, they finished 7th that year, 21 games behind the pennant winners, the Milwaukee Braves.
They used a 5-man starting staff that year, at least on paper. Drysdale, Podres, Koufax, Stan Williams, and Danny McDevitt. Drysdale started 44 games, Koufax 40, Podres 39, and Williams 37.