Born in San Francisco, California to Italian immigrant parents, Boccabella grew up in San Anselmo where he attended Marin Catholic High School. He attended college at the University of Santa Clara where, he was a member of the Santa Clara Broncos baseball team that made it to the final of the 1962 College World Series before losing to the Michigan Wolverines baseball team.

After graduating with an honors degree in commerce, he was signed by the Chicago Cubs before the start of the 1963 season and assigned to the Pocatello Chiefs, a Cubs farm team in the Pioneer League. Boccabella had an impressive first season in professional baseball, posting a .365 batting average along with 30 home runs and 92 RBIs in just 84 games with the Chiefs.

His performance earned him a promotion to the major leagues where he made his debut as a first baseman with the Cubs on September 2, 1963 at the age of 22. Despite hailing from San Francisco, the Cubs' radio announcers dubbed him "Boccabella from 'Pocatella'". In 1966, Cubs manager, Leo Durocher made the decision to convert Boccabella into a catcher to serve as a backup for Randy Hundley.

...
Wikipedia