Petry was a consistent, durable starter for nearly a decade in Detroit, winning at least 10 games in six consecutive seasons and at least 15 in four. He was 19-11 in 1983, leading AL pitchers with 38 starts, and 18-8, 3.24 in 1984 as the number-two starter for the World Champion Detroit Tigers. Petry lost Game Two of the WS to the Padres (Detroit’s only loss in the Series), and was the starter in the deciding Game Five, but got no decision.
In 1985 Petry was 15-13 while pitching over 230 innings for the fourth straight season, but in 1986 he went on the DL for the first time in his ML career, missing over two months after having bone chips removed from his elbow. Petry’s ERA ballooned to 5.61 in 1987 and he was traded to California for outfielder Gary Pettis after the season. In 1988 he spent two more months on the DL and won only three games in 22 starts for the Angels.
He enjoyed a mini-renaissance with the Tigers in 1990, going 10-9 in 23 starts, but bounced from Detroit to the Atlanta Braves to the Boston Red Sox during the 1991 season, and retired soon afterwards.