Neither Polamalu, who is nursing a strained right calf, nor Harrison, who is recovering from a minor procedure on his left knee, practiced this week. Steelers coach Mike Tomlin typically does not let players who did not participate during the week play in the ensuing game.
Harrison, who hasn't suited up for a game since a playoff loss to Denver last January, said he "felt great" but allowed there's a risk in coming back too quickly. The knee has been bothering Harrison since minicamp, and he underwent arthroscopic surgery on Aug. 15.
"What it comes down to is that there's no need to hurry up and rush yourself back and end up doing more damage so you have to deal with the injury for the rest of the season, instead of saying that you'll sit out a few weeks and get it back healthy rather than to go play a game, reinjure it," Harrison said.
Polamalu declined to speculate on his status but added that although he could "do mental repetitions on the sideline" while watching the defense, it "would be better to be on the field."
The All-Pro has made 18 straight regular-season starts dating back to 2010.
Pittsburgh running back Rashard Mendenhall, who is recovering from a torn ACL in his right knee suffered in the 2011 regular-season finale against Cleveland, practiced all week but has been listed as doubtful, while linebacker Stevenson Sylvester is out with a left knee injury.