Bernie “Boom Boom” Geoffrion, the hockey Hall of Famer credited with inventing the slap shot, died Saturday, shortly before his no. 5 jersey was retired by the Montreal Canadiens.

Geoffrion, who helped lead powerhouse Montreal teams to six Stanley Cups in the 1950s and early ’60s, died after a brief battle with stomach cancer. He was 75.

The Canadiens went ahead with the ceremony before Saturday night’s game against the New York Rangers. Geoffrion’s wife, Marlene, his three children, and his grandchildren were in attendance.

His number went up next to the no. 7 of Marlene’s father, Canadiens great Howie Morenz, just as Geoffrion predicted many years ago when the couple was dating.

Geoffrion was the first coach of the Atlanta (now Calgary) Flames, guiding the team to the playoffs in only their second season. He also had brief coaching stints with both the Rangers and Canadiens.

But it was as a player that Geoffrion really stood out. He was the first to bring his stick far above his head when shooting, creating a powerful shot that gave led to his nickname – the sound of his stick hitting the puck made a boom and the sound of the puck hitting the boards made another boom.

Geoffrion was a scoring star on Canadiens teams that also featured Hall of Famers Maurice “Rocket” Richard, Jean Beliveau, Doug Harvey, and Jacques Plante. Montreal won a record five straight Stanley Cups from 1956-60.

In 1960-61, Geoffrion won the Hart Trophy as the league’s MVP after joining Richard as the only players to score 50 goals in a season.

Born in Montreal on February 16, 1931, Geoffrion played 16 seasons in the NHL, including 14 with the Canadiens. After a two-year retirement, he made a comeback with the Rangers in 1966. He retired for good following the 1968 season, finishing his career with 393 goals and 429 assists in 883 regular season games. In 132 playoff games, he had 58 goals and 60 assists.

He was elected to the Hall of Fame in 1972, less than a month after being hired to coach the expansion Flames.