Cornelius Dennis "Mad Dog" Madigan (born October 4, 1934) is a Canadian retired professional ice hockey defenceman notable for being the oldest rookie in National Hockey League (NHL) history. Dennis was born in Port Arthur, Ontario. After playing several years in senior leagues in Ontario and British Columbia in the late 1950s, Madigan had a lengthy career as a minor league star, most notably with the Fort Wayne Komets of the International Hockey League for three seasons in the early 1960s, and then for the Portland Buckaroos of the Western Hockey League for nine seasons. He won accolades as First Team league All-Star in 1960, 1966, 1967, 1968 and 1969, Second Team All-Star in 1965, 1971 and 1972, as well as winning best defenceman honors in 1966.