Browns quarterback Baker Mayfield will not play Thursday night against the Broncos, the team announced Wednesday.
Case Keenum will start in place of Mayfield.
Mayfield had said Wednesday that he expected to play despite dealing with a torn labrum in his left shoulder. But the team ruled him out one day later.
Mayfield underwent an MRI earlier this week on his left shoulder after re-injuring it on Sunday against the Cardinals when taking a hit by J.J. Watt.
It was initially reported that Mayfield suffered a partially torn labrum in his left shoulder in Week 2. But Mayfield said Tuesday that it was a fully torn labrum.
Keenum, 33, is in his second year with the franchise. He has appeared in two games this season, but has thrown just three passes.
Mayfield had not missed a game in his professional career. On the season, he has thrown for 1,474 yards and tossed six touchdowns and three interceptions.
Cleveland will also be without starting running backs Kareem Hunt and Nick Chubb. Both are dealing with calf injuries.
Cleveland enters Thursday Night Football 3-3 and tied for third place in the AFC North.
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