GREEN BAY, Wis. (AP) Tweaks to the Packers' defense at midseason left Green Bay stronger against the run - and left opposing offenses with a new question to answer.
Where is Clay Matthews?
That is the predicament that the Dallas Cowboys face on Sunday in a marquee playoff game against the Packers at Lambeau Field.
''When you get to the nuts and bolts of it, they're an aggressive, attacking-style defense,'' Cowboys quarterback Tony Romo said. ''They're moving people around and putting them in great positions to succeed.''
None more so of late than Matthews, who, until this year, was known more for his prolific ability to get to the quarterback from the edge. The long-haired linebacker has been a headache for offensive tackles since coming into the NFL in 2009.
Matthews is still getting his sacks, though he's not just an outside linebacker anymore.
The Packers started playing Matthews more at inside linebacker at midseason, on the heels of a 44-23 loss Oct. 26 at New Orleans. Mark Ingram ran for 172 yards on 24 carries.
Coach Mike McCarthy was looking to shore up a league-worst run defense. A bye week followed the Saints game before the Packers unveiled the new wrinkle on Nov. 9 against Chicago - the same team that ran for 235 yards in the teams' first meeting in Week 4.
The move turned out to be a smashing success.
The Bears finished with 55 yards rushing on 24 carries, while Matthews recorded a season-high 11 tackles and a sack in the Packers' 55-14 rout. Overall, the defense allowed 3.60 yards a carry in the second half of the season, down from 4.78 in the first half.
''Obviously, we understand this is playoff football. However, we don't want to treat this thing any differently,'' Matthews said. ''We've been doing some good things and obviously there's room for improvement.''
The run defense has stiffened just in time to face DeMarco Murray, the league's leading rusher. While the Cowboys pose a threat in the passing game, too, coach Jason Garrett could elect to give Murray more handoffs to help control tempo and keep the ball out of the hands of Packers quarterback Aaron Rodgers.
''Yeah, especially with the weather and how we're going into this game, we know we have to stop the run,'' Matthews said. ''Whether that means they're going to run it 20-plus times, we just have to do a good job of going out there and setting the tone early.''
Matthews' move receives the most attention, though the Packers made other changes. Most notably, Sam Barrington is getting more snaps at inside linebacker, at the expense of playing time for veteran A.J. Hawk.
Moving Matthews allowed the Packers to give more playing time on the outside to Nick Perry and Mike Neal. Defensive tackle Letroy Guion has emerged as a key cog up the middle, while safety Morgan Burnett is having his best season in the league.
The focus on the run doesn't mean that Matthews isn't rushing the quarterback. On passing downs, Matthews has often returned to his familiar role of rushing from the outside.
He could be rushing from the inside, too. Whatever Matthews is doing is working, because he has 6 1/2 sacks over his last four games.
''We put a lot on his plate and he's handled it extremely well. Not many guys can do the things that he does,'' defensive coordinator Dom Capers said.
Matthews doesn't mind the workload. He's happy to contribute from anywhere on the field.
''I feel real good about when my package is called to go back (to inside linebacker) and help shore things up. I feel good about that as well as coming off the edge,'' Matthews said. ''At the end of the day, it's all about stopping the offense.''
Notes: Aaron Rodgers (calf) was listed as probable. The Packers didn't practice Friday, though coach Mike McCarthy said his quarterback looked fine in limited work Thursday. ... CB Davon House (shoulder), who missed the last three games, is probable. The 6-foot House has played well against tall receivers, which could help the Packers against Dallas wideout Dez Bryant.
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