The chances of Zach Collaros starting Saturday's CFL East semifinal against the Toronto Argonauts went down on Tuesday.
The Winnipeg Blue Bombers star quarterback was in street clothes for the team's first practice of the week after suffering a rib injury, the team announced.
Dru Brown was taking first-team reps at quarterback.
Collaros exited last Friday's must-win game against the B.C. Lions with an apparent injury after he was levelled by Lions defensive lineman Nathan Cherry late in the third quarter. He was lying on the field getting looked at by trainers for several minutes before walking to the medical tent on the sideline.
Brown then replaced Collaros at quarterback and led the Blue Bombers to a 34-10 victory. He completed all 11 of his passes for 185 yards and two touchdowns.
The CFL's Most Outstanding Player in 2021 and '22, Collaros has missed six games because of injuries this season.
Brown started both games against the Argonauts in the regular season, going 1-1.
The Argos host the East semifinal Saturday at BMO Field at 1 p.m. ET / 10 a.m. PT.
