He served as a coach in Major League Baseball for 12 seasons (1946–1957) with the Boston / Milwaukee Braves.

Born in St. Louis, Missouri, Keely stood 6' (183 cm) tall, weighed 175 pounds (79 kg), and threw and batted right-handed.

During World War II, he joined the St. Louis Cardinals as the club's bullpen catcher — an extra hand who caught relief pitchers and batting practice.

Keely formally became a major-league coach when he joined manager Billy Southworth in moving from the Cardinals to the Braves in 1946.

He was the Braves' bullpen coach through the 1957 season, serving in both Boston and Milwaukee and under four different managers.