Larocque played junior hockey with the Ottawa 67's of the Ontario Hockey Association from 1968 to 1972, and led the league in shutouts for the last three of those years. He was also one of the most penalized goalies, and was regularly involved in fights. In 1972, he was selected sixth overall by the Montreal Canadiens in the 1972 NHL Amateur Draft. In 1973 he played with the Nova Scotia Voyageurs of the American Hockey League, his first taste of professional hockey. For his outstanding play, Larocque was awarded the Hap Holmes Memorial Award with teammate Michel Deguise, and was selected to the Second All-Star Team. Larocque started his National Hockey League career in 1974 with the Canadiens. That was the season that Ken Dryden, one of the top goalies in that era, sat out to complete his law degree. Larocque shared playing time during the season with Michel Plasse and Wayne Thomas, but was the starting goalie in the playoffs. Dryden returned in 1975, and Larocque settled down as his back-up, sharing four Vezina Trophy wins, in an era when the award was given to the principal goalies on the team allowing the fewest goals in the regular season. The first three were largely because of Dryden's all-star play. In 1977, Larocque led the NHL with a 2.09 goals against average, but with Dryden ahead of him in the Canadiens net, he only managed to play 26 games. The Canadiens won four Stanley Cups during that stretch, but Larocque's only action in the playoff was for one period in the 1979 playoffs; Dryden was in front of the nets the rest of the time. The Stanley Cup wins were in 1976, 1977, 1978 and 1979. In 1979, Dryden retired. Larocque saw more action as a result, and won his fourth and final Vezina Trophy, sharing duties with Richard Sevigny and newly-acquired Denis Herron in 1981. Near the trade deadline during that season, he was traded to the Toronto Maple Leafs for defenceman Robert Picard. Larocque played 50 games the following season with a struggling Leafs team. Larocque was in net when the Buffalo Sabres scored a NHL record of 9 goals in one period in a 14-4 game. He was again traded, this time to the Philadelphia Flyers in 1983, in return for goaltender Rick St. Croix, and finished his NHL career with the St. Louis Blues in 1984 after being sold by the Flyers, who had settled on Pelle Lindbergh in goal. Larocque retired from hockey in 1985 after playing 13 games with the Peoria Rivermen in the International Hockey League.
