Yesterday, the Giants made it official, ruling their starting running back out with a knee injury for the game against the Dallas Cowboys in Irving, Texas.

"We just don't think that he will be ready," coach Tom Coughlin said, when asked if the team is taking a cautious approach with Jacobs.

But with the playoffs approaching quickly for the NFC East champions, sitting out this week will give Jacobs a chance to rest his nagging left knee injury - which has been bothering him since Week 5 and was reaggravated last week against Philadelphia - for when it matters most.

In Jacobs' place, Derrick Ward and Ahmad Bradshaw will handle the running duties against a Dallas defense that gave up 200 yards on the ground when the teams met in Week 9. Danny Ware could also get his first chance on offense this season, potentially coming in as the third back like Bradshaw usually does.

"We've been preparing to be without (Jacobs) this weekend," Bradshaw said. "(The scheme) is no different, it's just a different guy pretty much. Earth, Wind & Fire are all different, but we can all handle the job."

The Giants run the same plays no matter who is in the backfield. But they could see a difference in the Cowboys defense. Earlier in the week, Ward - who only talks to the media on Wednesdays - said when Jacobs isn't in the game, opposing defenses change and don't put as many men in the box.

Jacobs has missed one game this season, against the Cardinals in Week 12, when the Giants passed their way to a 37-29 victory. For the past few weeks, opponents have keyed in on the Giants' running game, and it has been less productive than usual, something the team has been looking to turn around.

Without Jacobs, aka "Earth," another element might be added to the mix: "Water," which Ware calls himself because he says his running style has aspects of the liquid, solid and vapor states.

After an impressive preseason, Ware has only been active for three games and hasn't had any carries. But this week in practice, Ware said he took some reps with the starters, which he usually doesn't do.

"You still never know until game day, but they've pretty much been getting me ready for an opportunity," Ware said. "I've been kind of just ready to go in at any moment. But we're so deep, I've just got to be patient, and whenever it's my chance, I've just got to make the most of it."

* Notes: WR Domenik Hixon (ankle/foot) and DT Fred Robbins (shoulder) were limited in practice yesterday and are listed as questionable for tomorrow. After the trainers held Hixon out Wednesday and Thursday, Coughlin said he worked half the practice yesterday and "seemed to feel pretty good about where he was." Robbins was added to the injury report yesterday after practicing all week. ...

Bradshaw (neck), CB Aaron Ross (ankle), DE Justin Tuck (lower leg) and T Kareem McKenzie (back) are all probable. Tuck was the only one of the four who was limited yesterday. LB Jonathan Goff (hamstring) is also out. ...

For Dallas, G Montrae Holland (ankle) and CB Adam Jones (neck) are out. RB Marion Barber (toe) was limited in practice and is questionable, as is WR Miles Austin (knee). Eleven Cowboys are probable, including TE Jason Witten (ankle), WR Roy Williams (foot) and LB DeMarcus Ware (knee). ...

Coughlin said he hasn't paid much attention to the reports out of Dallas of a rift on the Cowboys, stemming from tension between WR Terrell Owens and QB Tony Romo.

"I'm told, and I look at the information that is presented to me," Coughlin said. "But for me, right now, that has nothing to do with our team."

Jenny Vrentas may be reached at jvrentas@starledger.com