Teasdale signed a three-year, entry-level contract with the Montreal Canadiens on September 21, 2018.[4]
Prior to what would have been his first professional season in 2019–20, Teasdale suffered torn ligaments in his right knee during off-season training.[5] He was initially projected to miss a minimum of seven months. However, he ended up missing the entire season.
On July 13, 2022, Teasdale signed a one-year contract extension with Montreal.[6] Near the end of his third season playing for the Laval Rocket, Teasdale was recalled by Montreal and made his NHL debut against the New York Islanders on April 12, 2023.[7][8]
Following the season, Montreal did not tender him a qualifying offer, making Teasdale an unrestricted free agent.[9] He signed a one-year contract with the Iowa Wild on August 7, 2023.[10]
On September 6, 2024, Teasdale signed a professional tryout contract with the Syracuse Crunch.[11]