Blake played junior and senior hockey in the Sudbury area and was part of the 1932 Memorial Cup champions, the Sudbury Cub Wolves. He played for the Hamilton Tigers of the Ontario Hockey Association during the 1934–35 season before he signed with the Montreal Maroons of the National Hockey League on February 22, 1935; he made his NHL debut two days later on February 24, against the Chicago Black Hawks. Blake played eight games with the Maroons in the season, but was held scoreless; he did not play in any of the team's playoff games, but when the Maroons won the Stanley Cup, Blake's name was added to the trophy. Blake then played for the Canadiens until his retirement in 1948. He won the Hart Memorial Trophy as the NHL's Most Valuable Player in ; that same year he was also the league scoring champion with 47 points. For the last eight seasons, he was team captain, and led the Canadiens to Stanley Cups in 1944 and 1946. In the latter year, in which he incurred only one minor penalty, he became the first Canadien ever to win the Lady Byng Memorial Trophy for sportsmanship, which only Mats Näslund has replicated since as of 2015 (in ).