IRVING, Texas (AP) -- The Dallas running game is stuck in neutral without running back DeMarco Murray.
Of course, the Cowboys have also had a temporary center and backups starting at two other spots on the offensive line. And they fall behind almost every week.
Any of the above could explain why Dallas has the NFL's worst rushing offense, and one of the most overworked quarterbacks in Tony Romo.
"We've got to run the ball better. We've got to run the ball more," coach Jason Garrett said. "We have to be effective running the ball early in the ballgame so we don't get behind."
Probably easier said than done, particularly if Murray misses his seventh straight game Sunday night against Philadelphia. He last played against Baltimore on Oct. 14, when the Cowboys rushed for more yards than the defense-first Ravens have ever allowed in a game. That 227-yard day was marred by Murray spraining his right foot in the first half and the Dallas running game hasn't been the same since.
The only time the Cowboys have rushed for more than 100 yards in the past six games, they barely made it, getting 101 in a victory at Philadelphia. Felix Jones led Dallas with 71 yards, but his next-highest total filling in for Murray is 44 yards. For the season, Dallas is averaging 79 yards rushing per game.
The question of when Murray will return appears no more settled now than it was a month ago. He has been on the practice field in uniform consistently for warmups, and even said two weeks ago there was "a chance" he could play against Cleveland. But then he wasn't on the field at all for the last practice before the Thanksgiving Day loss to Washington.
"It shouldn't matter who's back there," said offensive lineman Mackenzy Bernadeau. "We should be able to make it clean for them to make the read and hit the holes. We miss him, but at the same time ... there are no excuses. We have to get better."
Bernadeau signed as a free agent in the offseason to play guard for Dallas. The 38-31 loss to Washington was his second start at center while the Cowboys wait for Phil Costa and Ryan Cook to get healthy. Cook came over in a late preseason trade with Miami because the Cowboys were already having trouble with injuries in the offensive line.
In Bernadeau's first start at center against Cleveland, left tackle Tyron Smith went out early with a sprained ankle and didn't play five days later against the Redskins. Jermey Parnell, an undrafted second-year player, took Smith's place, while veteran Derrick Dockery has filled Bernadeau's guard spot.
"We've had some injuries, but that's no excuse for us not being able to run the ball," said Lance Dunbar, an undrafted rookie who has overtaken Phillip Tanner as the third running back. "We've been working on it, trying to figure out things that are helping us and hurting us and just trying to fix things."
The Cowboys could start by avoiding big first-half deficits. Dallas has trailed by double digits before halftime in four consecutive home games. Two of those situations were desperate -- down 23-0 to the New York Giants, when Dallas had 19 yards rushing on 17 carries, and 28-3 to Washington, when the Cowboys had a season-low 11 carries.
Dallas abandoned the run for obvious reasons against Washington, but also leaned heavily on Romo while facing just a 13-0 deficit the previous game against Cleveland. It made sense because the Cowboys had 17 rushing yards on eight carries in the first half. Dallas ran just six times on three straight scoring drives in the second half, sending Romo on his way to 112 passes in a five-day span.
Romo has 456 pass attempts, or 41 per game, second only to Detroit's Matthew Stafford.
"What you're trying to do is find some plays you like and execute them," Garrett said. "You've got to be careful about saying, 'I'm going to lean on Tony and let him kind of go save the day.' It's too challenging of a position to do that."
Garrett doesn't want to wait for Murray to save the day either.
"We have to be able to run the ball if he's not able to go," Garrett said. "That's with Felix, that's with Dunbar, that's with Tanner, whoever's the runner. We just have to do a better job."
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