Thomas Henry Timmermann (born May 12, 1940) is a former American baseball player. He played professional baseball for 15 years from 1960 to 1974, including six seasons in Major League Baseball as a pitcher for the Detroit Tigers (1969–1973) and Cleveland Indians (1973–1974). He compiled a 35–35 win–loss record and a 3.78 earned run average (ERA), and recorded 35 saves and 315 strikeouts, in 228 major league games and 548 innings pitched.