William Robert Singer (born April 24, 1944) is an American former professional baseball pitcher with a 14-year career from 1964 to 1977. He played primarily for the Los Angeles Dodgers (1964–72) and the California Angels (1973–75), spending his final two seasons with the Texas Rangers (1976), Minnesota Twins (1976), and Toronto Blue Jays (1977). His nicknames included "Sing Sing," "Billy No-No" and "The Singer Throwing Machine."