Denis Charles Potvin is a Canadian former professional ice hockey defenceman and team captain for the New York Islanders of the National Hockey League (NHL). He is a four-time Stanley Cup winner as a member of the early 1980s New York Islanders. Potvin is also a three-time James Norris Memorial Trophy winner as the NHL's top defenceman. He was elected to the Hockey Hall of Fame in 1991 and served as a commentator for Ottawa Senators' television broadcasts on Sportsnet. Potvin is the former color commentator for the Florida Panthers. In 2017, he was named one of the "100 Greatest NHL Players" in history.

Defence or defense in ice hockey is a player position that is primarily responsible for preventing the opposing team from scoring. They are often referred to as defencemen, D, D-men or blueliners. They were once called cover-point.