Rashard Mendenhall's right knee injury has gone from "will need an MRI" to "could be a torn ACL" in record time. ESPN's Adam Schefter reports that the Steelers do not expect Mendenhall to play against the Denver Broncos in next week's AFC Wild Card round match-up, and Scott Brown of the Pittsburgh Tribune-Review reports that Steelers coach Mike Tomlin thinks Mendenhall's injury could be a torn ACL.

If Tomlin's fears are confirmed, that leaves the Steelers without the most important cog of their running game as they attempt to repeat as the AFC's Super Bowl representatives in the 2011 NFL playoffs. Mendenhall had 928 rushing yards in the regular season; every other Steelers runner combined had a total of 975 rushing yards.

Pittsburgh's offense is not a run-first one, nor one that is overly dependent on Mendenhall, thanks to Ben Roethlisberger, Mike Wallace, and Antonio Brown. But Mendenhall's loss might damage their chances in the playoffs substantially.

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