John Frederick Hiller (born April 8, 1943) is a former left-handed relief pitcher in Major League Baseball who played his entire career for the Detroit Tigers. His nickname was ratso. After suffering a heart attack in 1971, he returned to the team and recorded 38 saves in 1973 – a major league record until 1983, and a team record until 2000. He also set an American League record by winning 17 games in relief in 1974. His 125 career saves ranked fourth in AL history and were the seventh most among all left-handers when he retired, and stood as a team record until 1993. His 545 career games pitched ranked ninth among AL left-handers at the end of his career, and remain the franchise record.
Hiller grew up in Scarborough, Ontario, and after signing with the Tigers in 1962, he broke in with the team in 1965, but didn't see substantial play until 1967 when he appeared in 23 games. He pitched in 39 games for the 1968 pennant winners, posting a 9–6 record with 2 saves and a 2.39 earned run average. He had two unsuccessful relief appearances in the 1968 World Series against the St. Louis Cardinals, pitching the last two innings in the 7–3 Game 3 loss and facing five batters without recording an out in Game 4, a 10–1 loss. He allowed six hits and three walks, posting a 13.50 ERA, but the Tigers recovered to win the Series in seven games.
After his January 11, 1971 heart attack, he had a lengthy recovery and was invited to 1972 spring training, but was left off the roster and designated as a coach when the year began, starting the season as a batting practice pitcher. He rejoined the team in July, and had a 2.03 ERA in 24 games with 3 saves; his sole win came in a pivotal start, beating the Milwaukee Brewers 5–1 in the last weekend as the Tigers drove to the Eastern Division title. He pitched in three games in the 1972 American League Championship Series against the Oakland Athletics, winning Game 4 when Detroit scored three times in the bottom of the 10th inning to win 4–3.
During the 1977 season, Hiller was pitching for the Tigers in a game against the Seattle Mariners, who at the time were a first-year expansion team playing their home games in the Seattle Kingdome. The Kingdome had huge speakers hanging from its roof, in which a batted ball could very easily hit. Hiller gave up what appeared to be a game-winning home run to former teammate Willie Horton, but the ball hit one of the speakers and bounded back onto the field. In his post-game interview, Hiller was quoted as saying, "If a ball hits one of those (speakers) and saves a game for a pitcher, he ought to go to church the next day. I guess you know where I'll be tomorrow!"