When the Giants signed Brandon Jacobs in early September they likely didn’t envision he’d eventually be their starting running back.

But that’s the role Jacobs will play on Thursday in Chicago. David Wilson who injured his neck in Sunday’s loss to the Eagles did not practice Tuesday and has been ruled out. Offensive coordinator Kevin Gilbride confirmed Tuesday that Jacobs will start. “It’ll be a challenge” Gilbride said. “It’s a challenge if you had everybody because they’re such a talented defense. They’re powerful and strong. It’s going to be difficult but we’ll see what happens.”

Coach Tom Coughlin said Wilson’s status was “week-to-week” and two sources with knowledge said the second-year runner is going to get a second opinion on his neck next week.

The Giants also re-signed backup RB Da’Rel Scott who was waived a week earlier. But the bulk of the load could fall to Jacobs who replaced an injured Wilson last Sunday and rushed for 37 yards on 11 carries his largest workload since Dec. 11 2011. Jacobs has rushed for just 48 yards on 22 carries this season but he said he can handle the extra carries on Thursday.

“There’s no question” he said. “I’d be hurting the next day I’m not going to lie but I can definitely handle a full workload if I need to. I’m in good shape just whatever they ask me to do.”

Last Sunday Wilson didn’t think his neck injury was serious. Two days later it might be. Wilson’s neck injury is worrisome enough that he will seek a second opinion from an outside doctor two sources familiar with the situation indicated on Tuesday. The second opinion will come early next week according to one source.

Coughlin added that seventh-round pick Michael Cox was progressing and could contribute down the road as well.

“Brandon had some good runs the other day and Da’Rel had some good runs when he was here” Coughlin said. “We have the young rookie that’s done a good job in preseason on kickoff returns so I’m trying to project that further down the road. He did a nice job last week by the way scout team-wise.”