THIS DATE IN HISTORY: Sept. 25
1926: The NHL officially approves franchises in Chicago and Detroit for the 1926-27 season. Along with a second franchise awarded earlier to New York, the NHL becomes a 10-team league and soon adopts a two-division format.
The Detroit team calls itself the Cougars after purchasing players from the Victoria Cougars of the Western Hockey League, which ceases operations after the 1925-26 season. The franchise changes its name to Falcons in 1930 before becoming known as the Red Wings two years later.
The Chicago franchise is granted to Major Frederic McLaughlin, who names the team in honor of his military unit in World War I. It's known as the Black Hawks until 1986, when the name is changed to Blackhawks.
Detroit, Chicago and the expansion franchise in New York, known as the Rangers, are placed in a new American Division with Boston and Pittsburgh. The four Canadian teams and the second-year New York Americans are placed in the Canadian Division.
1984: Phil Esposito, Jacques Lemaire and Bernie Parent, three stars of the 1970s, are among five inductees to the Hockey Hall of Fame. Also inducted are longtime NHL executive Jake Milford and Punch Imlach, the architect of the Toronto Maple Leafs' four Stanley Cup championships in the 1960s.
1987: Denis Potvin, holder of the NHL career records for goals, assists and points by a defenseman, announces he will retire after the 1987-88 season, his 15th with the New York Islanders. Potvin, a three-time Norris Trophy winner, is one of the few remaining veterans from the teams that win the Stanley Cup for four consecutive years in the early 1980s. He is named to the 100 Greatest NHL Players in 2017.
Video: Denis Potvin was captain of Islanders' 1980s dynasty