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With a sagging running game weighing down an otherwise effective offense, the Steelers will get perhaps the boost it needs with the return of running back Rashard Mendenhall in Week 5 when Philadelphia comes to town.
Mendenhall tore the ACL in his right knee in Week 17 of the 2011 season after a reception against Cleveland. He's been practicing, but hasn't been active in a game in 2012.
The Steelers running backs have struggled in the team's first three games (1-2). Isaac Redman leads the team with 72 yards on 32 carries - an average of 2.3 yards per carry. Jonathan Dwyer has 70 yards on 24 carries.
The longest run by a running back is 13 yards by Redman on a play his knee appeared to be down against the Jets in Week 2. Redman and Dwyer have rushed for nine first downs on 56 carries.
Mendenhall has 2,201 yards and 22 touchdowns in his last 31 games.
Minnesota's Adrian Peterson has played in each of the Vikings' four games this season after tearing his ACL late in the 2011 season. Peterson doesn't look as explosive as he's been throughout his career - and Mendenhall, like everyone else, isn't as dominant a runner as Peterson has been when healthy - but he's contributed to a reasonably successful Vikings running game.
The smallish long rush number for the Steelers combined with a miserable 2.6 yards per carry average can be attributed to the lack of one long run this season. Mendenhall, when healthy, is clearly the running back with breakaway speed between himself, Redman and Dwyer. If he's able to make a defender miss in the hole, or evade a tackler to the outside, he could be the big play threat the Steelers are missing in their backfield.