In 1942, the Tigers gave exclusive broadcast rights to WXYZ, making Heilmann the exclusive radio voice of the Tigers in Detroit and throughout Michigan. He was the voice of the Tigers in 1940 and 1945 when the Tigers won the American League pennant and won the 1945 World Series over the Chicago Cubs. He became known for his gift as a story-teller and for his knowledge of the game. In 1951, "Detroit Free Press" sports editor Lyall Smith described Heilmann's broadcasting style: