Steelers safety Troy Polamalu's status for the remainder of the season is in doubt. He left Sunday's game against the Bengals with a left knee injury. "Not Troy. Not again," safety Ryan Clark said. Pittsburgh coach Mike Tomlin only revealed that Polamalu went to the hospital for an MRI. He was just working himself back into the lineup after suffering an injury to the same knee in the team's season opener. "Troy isn't just the best player on our team," Clark said. "He's the best player in the league. ... "If he's only out a week or two, the defense probably can sustain and win games. But if he's out longer? Playing against the [Baltimore] Ravens twice? That would be tough. "But this is the NFL. One way or the other, you've got to go on. No one is going to say, 'Y'all lost Troy. We'll give you a break.' It doesn't work that way. Nobody is going to feel sorry for us."