[8] Sirois was able to be added to the roster, due to the Impact being a Canadian team as well, which meant his ITC was already in Canada, as well as already being in the bubble.
[9] Upon completion of the 2021 MLS season, CF Montréal announced that they would exercise the option on Sirois' contract for 2022.
[20][21] On February 25, 2023, Sirois made his competitive debut for Montreal, entering as an injury replacement for James Pantemis.
[22][23] After winning the starting goalkeeper role with Montreal, Sirois would sign a three-year contract extension with the club, with an option for the 2027 season.
[26] In March 2024, Sirois was called up to Canada's squad for their 2024 Copa América qualifying play-offs against Trinidad and Tobago.