Safety Troy Polamalu, whose injured knee swelled after a teammate rolled into him at Wednesday's practice, did not practice yesterday and likely will not play in tomorrow against the New England Patriots.

Polamalu was given a run test in the morning to determine if he would be able to practice, but there was no change in his condition and it appears he will be unable to play.

He is listed as doubtful on the team's official injury report.

"We'll see how it feels on Sunday," Polamalu said.

Polamalu, a three-time Pro Bowl safety, has a sprain of the medial collateral ligament and posterior cruciate ligament in his right knee -- the same type of injury that kept receiver Hines Ward out for three games earlier this season.

Polamalu has not played in the past two games. He was doing fine and was scheduled to return against the Patriots until his injury was aggravated two days ago, causing swelling.

He will be replaced in the starting lineup by safety Tyrone Carter.

"Ty has played consistently for us," said defensive coordinator Dick LeBeau. "He steps in there and we do everything we do with Troy."

Outside linebacker James Harrison missed practice for personal reasons, but he is expected to rejoin the team today and will play against the Patriots.

Receiver Santonio Holmes (ankle) and LT Marvel Smith (back), each of whom missed the past two games, practiced all week and will start. RB Najeh Davenport (foot) also has practiced all week and will play.

Backup LBs LaMarr Woodley (hamstring) and Andre Frazier (groin) are listed as questionable.

Ben Roethlisberger did more than overcome a slow start in the rain to bring the Steelers back from a 7-0 deficit against the Cincinnati Bengals.

He did what offensive coordinator Bruce Arians called "his best job of the season" calling protections and making changes at the line of scrimmage -- one of the reasons Roethlisberger was not sacked for the first time this season.

That will come in handy against the Patriots because they like to switch their defensive formations to confuse an offense.

"We ran a lot of no-huddle stuff for three or four series, so I had to call a lot of the protection at the line," said Roethlisberger, adding that he had to call and change protections approximately 15 to 20 times.

"When you see me waving my hands and pointing, that's what I'm doing -- sliding the protection."

Right tackle Willie Colon, whom the coaches say has been the second-best pass-protector behind Smith, had his best game of the season against the Bengals, shutting down DE Robert Geathers.

He will need more of that against defensive end Ty Warren, one of three first-round picks on the Patriots' defensive line.

"I'm at the stage where I stopped looking back and I look forward," said Colon, a first-year starter. "That's what coach Tomlin has talked to me about and that's what I'm doing.

"It's confidence. And I never take my job for granted. I'm just happy where I am, but there's a lot of room for improvement, a lot of room for me and [right guard] Kendall [Simmons] to work better together."

Mike Vrabel, a third-round draft choice by the Steelers in 1997, is reluctant to say this is the best Patriots team on which he has played.

After all, Vrabel has played on three Super-Bowl winning teams since signing with the Patriots as a free agent in 2001.

But he did acknowledge it's the most talented team.

"I don't think anybody can say that they have the best team they've ever had until the season is over, until the run through the playoffs and the Super Bowl," said Vrabel, third in the AFC with 9.5 sacks.

"I would look back to San Diego last year and I'm sure they thought they had a really, really good team. But I think if you asked them after the season, they would say that it wasn't because you have to win a championship to be considered that good of a team."