The Isaac Murphy Handicap is an American Thoroughbred horse race held annually in late June at Arlington Park racetrack in a suburb of Chicago, Illinois. The race is run on Polytrack synthetic dirt and is open to fillies and mares, age three and older who were bred in the State of Illinois. The race is named in honor of Isaac Burns Murphy, a U.S. Racing Hall of Fame jockey whom the Hall says "is considered one of the greatest race riders in American history." Isaac Murphy raced in Chicago and won the city's then very prestigious American Derby on four occasions. On turf: 1976, 1991–1996