The Pittsburgh Steelers' offense is a mess.
Their run game is horrendous, ranking 31st in yards and average gain.
Mike Wallace, their go-to deep threat at wide receiver, went to the Miami Dolphins in free agency last off-season.
Tight end Heath Miller, their 2012 MVP, has not played yet following last season's torn ACL.
Center Maurkice Pouncey, by far their best offensive lineman and a three-time Pro Bowl pick, was lost for the season in Week 1.
But the Steelers do still have quarterback Ben Roethlisberger, making them potentially dangerous.
In seven of his nine previous seasons, Roethlisberger has posted a passer rating above 90.0 while guiding the Steelers to the Super Bowl three times and winning it twice.
Over the past four seasons he has thrown 90 touchdown passes and just 39 interceptions while being sacked 152 times, four more times than Jay Cutler.
The virtually indestructible, 6-foot-5, 241-pound Roethlisberger often throws with enemy pass rushers hanging on him or close enough to inflict imminent harm.
A typical Roethlisberger completion seems to come only after he has shaken off or somehow eluded a pass rusher despite a style that is closer to hulking than nimble.
If Michael Vick is a jack rabbit, Roethlisberger is a water buffalo.
The 10-year veteran has struggled along with the rest of the Steelers (0-2), but he will be the focus of the Bears' defense Sunday night at Heinz Field.
"We have to be relentless to the ball," Bears coach Marc Trestman said. "We have to keep our contain lanes. Last week (Minnesota's Christian) Ponder got outside the pocket two or three times.
"Ben is really the best at it. There's a lot of faster quarterbacks in the league. But I don't know that there's been one any better over the last decade at extending plays under the chaos of a pass rush than Ben Roethlisberger, (or one who has) made bigger plays than he has over his career."
Roethlisberger won't break off any 20-yard runs when the pocket breaks down. But he will buy enough time to allow a receiver to get beyond the coverage and pick up 40 yards.
"He's a Hall of Fame-type quarterback," said Bears defensive coordinator Mel Tucker. "He makes plays with his feet. You have to keep him in the pocket. When he improvises, he's very, very dangerous.
"He's big, he's strong, he's not afraid to stand in there. He shakes guys off. It usually takes more than one guy. The first guy usually doesn't get it done, so we've got to get multiple guys on him.
"Even when you're hanging on the guy, he still makes a throw down the field. And when he scrambles, he's looking to throw. He can throw it 60 yards on the run. He's a rare guy in that way. It's going to be a huge challenge for us."
The Steelers' offense has missed Miller, who caught a team-best 71 passes for 816 yards and 8 touchdowns last season. He is expected back for Sunday night's game after practicing all week.
"To me, he's the best tight end in the league," Roethlisberger said. "It helps us in the run game, and obviously helps in the pass game. Just to have another guy that's been there helps."
Miller, Roethlisberger, safety Troy Polamalu and cornerback Ike Taylor are the only Steelers who have played in the Steelers' three Super Bowls since 2005.
But this year's team is in uncharted waters. In six previous seasons under coach Mike Tomlin, the Steelers have never started a season 0-2 and have never been two games under .500.
And they've never had more issues. Roethlisberger already has been sacked seven times, the offense has scored just 19 points, and the defense has just 2 sacks.
"Winning helps cure a lot of issues, and that's what we need to do is try and get a win," Roethlisberger said. "I've never started a season like this since I've been in Pittsburgh.
"It's a challenge for us, and it's one we're not going to back down from."
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