Roy was drafted in the third round, 51st overall, in the 1984 NHL Entry Draft by the Montreal Canadiens, a team he disliked, being a fan of the rival Quebec Nordiques. His grandmother Anna Peacock was a big Canadiens fan, but died before seeing her grandson being drafted. Roy kept playing for the Granby Bisons of the Quebec Major Junior Hockey League (QMJHL) before being called up by the Canadiens. Despite the thoughts that he was not going to play for the team, on February 23, 1985, he made his NHL debut when he replaced the Canadiens' starting goaltender, Doug Soetaert, in the game's third period. Roy played for 20 minutes and earned his first NHL win without allowing a goal. After the game, he was reassigned to the Sherbrooke Canadiens of the AHL. Despite starting as a backup, Roy replaced Greg Moffett after he had equipment troubles during a game. He earned a win, became the starting goaltender for the playoffs and led the team to a Calder Cup championship with ten wins in 13 games.