Les Moss's journey in professional baseball began when he debuted as a catcher in Major League Baseball (MLB) with the St. Louis Browns in 1946. Born in Tulsa, Oklahoma, Moss quickly established himself as a reliable presence behind the plate. Over the course of his playing career, he became known for his defensive skills and ability to handle pitchers effectively.

Moss spent the early years of his career with the Browns, a team that would later become the Baltimore Orioles. During his tenure with the Browns, he played alongside some of the era's notable players and gained valuable experience in the major leagues. His time with the Browns lasted until 1951, after which he was traded to the Boston Red Sox. However, his stint with the Red Sox was brief, and he soon found himself with the Detroit Tigers.

It was with the Tigers that Moss spent the majority of his playing career. From 1953 to 1958, he served as a dependable catcher for the team. While his offensive numbers were modest, his defensive capabilities and leadership on the field were assets to the Tigers' roster. Moss's ability to work with pitchers and manage the game from behind the plate earned him respect in the league.

After his playing days concluded, Moss transitioned into coaching and managing, where he continued to influence the game. He began his coaching career with the Chicago White Sox, serving as a bullpen coach and later as a pitching coach. His experience as a catcher provided him with insights into the intricacies of pitching, making him a valuable asset to the coaching staff.

Moss's managerial career began in the minor leagues, where he honed his skills and developed a reputation for nurturing young talent. His success in the minors eventually led to an opportunity to manage at the major league level. In 1979, he was appointed as the manager of the Chicago White Sox. Although his tenure as a major league manager was brief, it marked the culmination of a long and varied career in baseball.

Throughout his years in the sport, Moss was known for his steady presence and deep understanding of the game.