Cal Ermer's journey in professional baseball began as a player before transitioning into a managerial role. Born on November 10, 1923, in Baltimore, Maryland, Ermer's early years in baseball were spent as an infielder. He played in the minor leagues, where he demonstrated his skills on the field with various teams. His playing career included stints with organizations such as the Washington Senators, where he played in the minor league system.

Although Ermer's time as a player in Major League Baseball was brief, appearing in only a few games for the Washington Senators in 1947, his career in baseball extended far beyond his playing days. After hanging up his cleats, Ermer found his calling in managing and coaching, where he spent the majority of his career.

Ermer's managerial career began in the minor leagues, where he managed several teams over the years. His leadership and understanding of the game were evident as he guided young players and helped develop their skills. One of his notable achievements came in 1961 when he managed the Charlotte Hornets, a minor league team, to a league championship. This success highlighted his ability to lead and mentor players effectively.

In 1967, Ermer was given the opportunity to manage at the major league level when he was appointed as the manager of the Minnesota Twins. Taking over the team late in the season, he led the Twins to a strong finish, narrowly missing out on the American League pennant. His tenure with the Twins continued into the 1968 season, but the team struggled, and he was replaced before the season concluded.

Despite the challenges faced during his time with the Twins, Ermer's influence in baseball continued as he returned to managing in the minor leagues. His career in baseball spanned several decades, during which he contributed to the development of many players who went on to have successful careers in the major leagues.