Steelers back-up quarterback Byron Leftwich was on the sideline seeing starter Ben Roethlisberger writhe around on the ground. He was holding his throwing arm gingerly.

Not something Leftwich - Roethlisberger's back-up off and on since 2008 - hasn't seen previously. He reportedly went over to Roethlisberger and said "if it's bad, just let me know."

Roethlisberger reportedly looked at him and nodded.

Injury embellisher or no, Roethlisberger plays through a lot of pain anyway. Leftwich knew the fact he responded non-verbally meant it was something significant. He would eventually leave for the hospital for a full MRI and x-rays, while Leftwich made his first appearance of the season.

Back-up quarterbacks are the most popular players in town when the starter struggles, and the most valuable on the team when the starter gets hurt. Leftwich prepares each week as a back-up; getting very limited reps, he knows his time to shine is when the unthinkable happens.

Leftwich, the seventh overall pick of the 2003 NFL Draft, has played on four different teams now as a starter and a back-up, and his veteran presence can help the Steelers' offense quickly adjust to what could be an extended absence of Roethlisberger.

Neither quarterback was outstanding against the tough pass rush of the Chiefs in Week 10, but Leftwich did get the Steelers down to field goal range, to take a 13-10 lead in the fourth quarter. Heading into the Steelers' clash with rival Baltimore, with time to prepare as the starter, Leftwich has an opportunity to step up in Roethlisberger's absence, and lead his team to victory in Week 11, like he did in Week 10.

The Steelers need to place Leftwich in a position to succeed against Baltimore, and the best way to do that will be to get the running game on track. Running the ball, and having an outstanding short-yardage tight end, are the quarterback's two best friends. Leftwich can hand off to any one of a trio of Steelers' running backs who have had success this year as well as find Heath Miller down the field.

His ability to manage this game and make plays down the field will go a long way in telling Pittsburgh's ability to defeat the AFC North-leading Ravens.

A win would put the Steelers in first place of the division for the first time since the end of the 2010 season.

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