Killinger was also a minor league baseball player from 1922 until 1932. During that time, he played for the Jersey City Skeeters (1922), Atlanta Crackers (1923), Harrisburg Senators (1924, 1927–1928), Shamokin Indians (1926) and the Williamsport Grays (1929–1932). He served as a manager for the Indians and the Senators.