Lestage had been drafted in the second round, tenth overall, by the Montreal Alouettes in the 2021 CFL Draft. After exhausting his National Football League opportunities, he signed with the Alouettes on July 31, 2022.[5] He soon after made his professional debut on August 4, 2022, against the Winnipeg Blue Bombers as a backup offensive lineman.[6] Lestage then made his first career start on September 23, 2023, against the Hamilton Tiger-Cats.[6] He played in 11 regular season games in 2022 and started the final six games of the season.[6]
In 2023, Lestage won a starting job in training camp and started 17 games during the regular season, while missing one game in July due to injury.[7] However, he suffered a knee injury near the end of the season and did not play in any post-season games that year and was on the injured list when the Alouettes won the 110th Grey Cup.[8] For his strong play in 2023, Lestage was the Alouettes' nominee for the CFL's Most Outstanding Offensive Lineman Award.[9]