Like his college teammate, future MLB utilityman and manager Joe Morgan, Roarke signed with the local National League club, the Boston Braves, in 1952.

After a brief stint with the Braves' Evansville farm club in the Class B Three-I League, Roarke entered the military, effectively delaying his professional debut until 1954.

Known as a good handler of pitchers and an excellent defensive catcher, Roarke struggled as a hitter, eclipsing a .250 batting average only three times in his seven-year minor league career.

He toiled one further season, 1960, in the minors (with the Denver Bears of the American Association) before finally making his Major League debut with the Tigers at age 30 on April 19, 1961.

Then, after a seven-year stint (1971–77) as a minor league manager and roving minor league pitching instructor, Roarke served as a pitching coach for the Chicago Cubs, St. Louis Cardinals (where he worked on two NL pennant winners—1985 and 1987—under Whitey Herzog), San Diego Padres and Boston Red Sox, retiring after the strike-shortened 1994 season.