IRVING, Texas - DeMarco Murray ranks first in yards per carry among the NFL's top 25 rushers. He has already run for more than 1,000 yards, easily the highest total in his three seasons in the NFL.

With quarterback Tony Romo suffering from what sources say is a herniated disk - and his prognosis for Sunday night against the Eagles is dreary at best - one might theorize that the Cowboys plan to alleviate prospective offensive woes with a heavier-than-usual dose of DeMarco.

Well, if that's true, they are playing their cards close to the vest.

Coach Jason Garrett, who would have his cards surgically implanted if possible, was presented with such a proposition.

"Not necessarily," he responded.

Offensive coordinator and play caller Bill Callahan claimed nothing would change should backup Kyle Orton take Romo's place in the decisive game of the season.

"We'll just keep doing what we've been doing," Callahan said before upping the stakes himself. "Shift to a whole new offense? That's not the situation at all."

No one suggested a seismic shift such as installing the wishbone. But maybe a few more carries for Murray, 10th in the league in rushing at 1,073 yards. He is also last among the top 10 in rushing attempts per game at 15.4. That's almost four fewer carries per game than league rushing leader LeSean McCoy of the Eagles, who has 1,476 yards. Murray leads McCoy in yards per carry, 5.4 to 5.1.

The Cowboys, it should be noted, are 11-0 over Murray's career when he gets at least 20 carries per game.

Garrett conceded that Murray "has certainly been playing very well. When he's been healthy for us, he's been a very good player over the course of his career. I think you can pick out chunks in every one of the seasons that he's played where he's made a huge impact on our team."

Of course, that is with the threat of Romo on the field. In playing with Orton, he might find defenders with different priorities.

Murray missed the Cowboys' first meeting of the season with the Eagles in Philadelphia with a knee injury. The Cowboys won, 17-3. He missed the next game as well, a 31-30 loss to Detroit.

He has been stellar in the Cowboys' last three games. He has rushed 58 times for 376 yards. That's 6.5 yards per carry.

Still, Murray said he has noticed not much different in the Cowboys' game plan this week. He said he has complete faith in Orton's ability to replace Romo. He said he was not anticipating more carries against the Eagles, let alone a workhorse load.

"I don't know how they're going to call it. That's up to Bill," he said, referring to Callahan. "I'm ready for whatever they ask me to do."

But he would welcome the opportunity to carry the load.

"If they do, then great. If they don't, then so be it. I'm preparing like I do any other week. I'm working hard, making sure I know my assignments, and knowing my keys and things of that nature, so I'll be ready."

Notes. Dez Bryant did not practice Thursday because of a bad back. But the team's leading receiver vowed he would play Sunday night.

"I'm good," Bryant said. "I'm playing. Don't worry about it."

Romo was seen walking around the team's Valley Ranch complex Thursday.

He did not practice and was not an integral part of any meeting. He spent the day rehabilitating his back on the slim chance he will be able to play.

If Romo doesn't practice Friday - and there are no expectations that he will - he still could play Sunday if he is cleared by the medical staff. But again, that is unlikely.