After graduating from high school, Hagar "wanted to get out of Fontana as quickly as I could". He moved to nearby Riverside and played in a handful of local bands, while also landing a job running the music department at a local store. Hagar first joined the Johnny Fortune Band as lead vocalist and rhythm guitarist and subsequently played in a string of other pre-Montrose bands including Big Bang, Skinny, Dustcloud, Cotton, Jimmy, the Justice Brothers, and Manhole. The Justice Brothers were the house band at a bar called "The Nightclub" in San Bernardino, before they relocated to San Francisco. During this period in Riverside, Hagar met drummer David Lauser, who would become his friend and musical partner for decades to come. Hagar then got married and moved to San Francisco. At some point after landing in San Francisco, two members of his band were arrested on drug charges, and Hagar found himself broke and without a band. He subsequently spent several months driving a dump truck for his father-in-law in New York as a means of supporting himself until he could put a new band together.