Dallas’ Murray will present big task for Seahawks’ front seven

RENTON, Wash. – While extolling the virtues of Seattle defensive tackle Brandon Mebane and his role in the team’s run defense Wednesday, teammate Richard Sherman finally settled on this:

“Brandon Mebane does not move. He is an immovable object.’’

The same, though, can pretty much be said of the entire Seattle front seven. After a dominating performance at Washington on Monday night, the Seahawks lead the NFL in run defense, allowing just 62.3 yards per game and 2.6 per attempt.

Now, the closest thing in the NFL to an unstoppable force arrives. Dallas running back DeMarco Murray leads the NFL with 670 yards and 134 per game, a pace that would set the all-time season rushing record with 2,144.

Murray and the Cowboys collide with Seattle’s defense Sunday at CenturyLink Field.

Last Sunday, Murray became the third NFL player in history to rush for 100 or more yards in each of his first five games, joining Jim Brown and O.J. Simpson. Only Brown, in 1958, did it in the first six games.

Seattle middle linebacker Bobby Wagner was asked Wednesday, “What’s the challenge Sunday when it comes to Murray?”

“Keep him under 100,’’ Wagner said.

Wagner said it with a little smile, and the line got some laughs from the assembled media.

But there was no questioning the seriousness of the intent behind Wagner’s statement.

The Seahawks know that Sunday’s winner will likely be determined by whether Dallas can run the ball on Seattle.

It’s not just the Cowboys’ running success that has caught Seattle’s eye —– Dallas’ average of 160 yards trails only Seattle’s 167.3 – but also the commitment to it.

Dallas, a team long led by the arm of Tony Romo, is suddenly running the ball more than any team in the NFL, averaging 32.6 attempts per game.

Wagner recalled watching film of Dallas’ game against St. Louis in which the Rams led 21-0.

“They were down, but they were still trying to run the ball,’’ Wagner said of a game the Cowboys rallied to win 34-31 while attempting 34 runs and 23 passes.

It’s a far cry from a year ago, when Dallas averaged 21 runs per game, 31st in the NFL.

It’s a switch in emphasis that only makes sense. Murray, a fourth-year pro out of Oklahoma, is paired with a rapidly improving offensive line that features three former first-round picks.

Among the first-rounders up front is left tackle Tyron Smith, who played for Seahawks coach Pete Carroll at USC.