Mark John Douglas Messier is a former ice hockey centerman of the National Hockey League. He spent a quarter of a century in the NHL with the Edmonton Oilers, New York Rangers, and Vancouver Canucks. He also played professionally with the World Hockey Association's Indianapolis Racers and Cincinnati Stingers. At the time of his retirement, he was the last former WHA player still active in professional hockey, as well as the last active player who had played in the NHL in the 1970s.

Messier is widely considered among the best NHL players of all time as well as among the greatest leaders in the game's history. He is second on the all-time career lists for regular season points , playoff points and regular season games played . He won five Stanley Cups with the Oilers, one with the Rangers, and is the only professional athlete to captain two different teams to championships. In 2007 he was inducted into the Hockey Hall of Fame.