Steelers safety Troy Polamalu will not play this weekend, according to a league source.
Polamalu has been out most of the season with a knee injury. He spoke earlier this week about it being doubtful he would return, and has now been ruled out.
Polamalu has been concerned about the knee. Team doctors had him targeted to play last week against Green Bay. But he informed the team last Wednesday that he was not comfortable and ended up sitting out that game as well.
The Steelers host Baltimore Sunday in a game that is crucial for both AFC North rivals as they seek a playoff spot.