John Carlson (born January 10, 1990) is an American professional ice hockey defenseman and alternate captain for the Washington Capitals of the National Hockey League (NHL). He was drafted by the Capitals in the first round, 27th overall, in the 2008 NHL Entry Draft after playing a year in the United States Hockey League (USHL) with the Indiana Ice. Before reaching the NHL, Carlson played junior hockey in the Ontario Hockey League (OHL) with the London Knights and played professionally with the Capitals' American Hockey League (AHL) affiliate, the Hershey Bears. He also participated internationally for the United States in the 2010 World Juniors and 2014 Winter Olympics. Carlson won the Stanley Cup as a member of the Capitals in 2018, as the highest scoring defenseman during the playoffs.