The twenty-year-old was injured before the official start of Canadiens training camp, which began on Thursday with team physicals.
The Canadiens' seventh-round pick (207th overall) in 2015, Addison suited up for 51 games with the OHL's Windsor Spitfires last season, registering 24 goals and 19 assists along with 62 penalty minutes. As co-captain of the team, the Brampton, ON native helped lead the Spitfires to the 2017 Memorial Cup championship, contributing five goals and an assist in four games.