Roethlisberger has been inactive since suffering injuries to his ribs and throwing shoulder in Week 10's meeting with the Kansas City Chiefs. In total, he was forced to miss three games (all of which were against division opponents), including two against the Baltimore Ravens.
After progressing last week, it was determined that Roethlisberger's arm strength would determine his availability for Week 13. Ultimately, Tomlin decided that Roethlisberger was not yet ready to return.
After participating in his second consecutive practice this week on Thursday, Tomlin was comfortable enough to allow Roethlisberger to play, via the Steelers' official site:
"He has been above the line in all areas," said Tomlin following Thursday's practice. "Really, the only question we can't answer is taking a hit. Obviously that will be answered in the stadium on Sunday.
"I am extremely comfortable with his ability to work the field both vertically and horizontally. He has great velocity on his ball. We're ready to go."
The Steelers have four games remaining this season, with its final two games coming against division opponents (the Cincinnati Bengals in Week 16 and Cleveland Browns in Week 17). The team currently sits in second place in the AFC North with a 7-5 record.