DETROIT — Pittsburgh Steelers safety Troy Polamalu missed a portion of practice again Friday because of a sore ankle, but remains listed as probable for the Super Bowl on Sunday.

Polamalu woke up Thursday with a sore ankle and, after being examined by team trainers, underwent an MRI exam.

"There was nothing really there," coach Bill Cowher said Friday. "Now he'll feel better. He'll be fine by Sunday."

Before practice began Friday at the Silverdome, Polamalu playfully lined up as a quarterback with several teammates and simulated throwing passes.

Wide receiver Hines Ward sat out the last half of practice with a sore shoulder, but only for precautionary reasons, according to Steelers spokesman Dave Lockett. Ward was not added to the team's daily injury report, the last before Sunday's game against Seattle.

Defensive end Travis Kirschke (groin), fullback Dan Kreider (knee) and linebacker James Harrison (ankle) also missed part of practice, but Kirschke and Kreider were upgraded from questionable to probable. Harrison remains listed as probable.

Friday was the Steelers' final full-scale practice before their second Super Bowl in 26 years. They will be limited to a walkthrough session Saturday.