Complex sentence: In 1965, he was promoted by Richards to manager of the newly rechristened Houston Astros, serving for the team's debut season in the Astrodome; he even briefly managed Baltimore in 1961 when Richards resigned that September to take the front office reins in Houston.
Split into simpler sentences: In 1965, he was promoted by Richards to manager of the newly rechristened Houston Astros, serving for the team's debut season in the Astrodome. It was actually his second major league managwerail job: he had briefly managed Baltimore in September 1961 when Richards resigned to take the front office reins in Houston.