With a playoff berth already locked up on Sunday afternoon, the Pittsburgh Steelers travel across the country to face the San Francisco 49ers on Monday Night Football. The Week 15 matchup is full of question marks - particularly at quarterback, where Ben Roethlisberger's status is still up in the air.

Big Ben's status will directly affect how much the Steelers lean on running back Rashard Mendenhall. Currently, the fantasy projection experts at numberFire.com project Mendenhall with a quiet 5.31 fantasy points against the 49ers. Unfortunately for Mendenhall, the Niners have the top ranked rushing defense in the league, having allowed less than 1,000 rushing yards through the first 14 weeks of the season.

For more news and notes on Pittsburgh, be sure to visit SB Nation's Steelers blog Behind the Steel Curtain. For a look behind enemy lines, check out SB Nation's 49ers blog Niners Nation and SB Nation Bay Area.

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