McLeod Bethel-Thompson will start on Friday in place of an injured Nick Arbuckle.
Arbuckle was a limited participant in practice on Wednesday due to a hamstring problem. He has since been added to the one-game injured list.
Bethel-Thompson started Toronto’s first two games of the season while Arbuckle worked his way back from a hamstring issue.
The 33-year-old went 1-1 in those starts, completing 44-of-69 pass attempts for 535 yards, three touchdowns, and no interceptions. He also carried the ball four times for 24 yards.
Montreal visits Toronto on Friday night with kickoff slated for 7:30 p.m. ET.