EAST RUTHERFORD, N.J. (AP) — The injury bug that has afflicted the NFC East-leading Giants’ defense since training camp will force yet another adjustment for Sunday night’s divisional clash with the Eagles.

Linebacker Michael Boley, who wears the headset helmet that connects him with defensive coordinator Perry Fewell, is doubtful with a hamstring strain sustained last week in San Francisco. Someone whom Fewell preferred not to identify will be wearing the wired-up helmet this week. But even more important will be the varied personnel groupings Fewell may have to throw out there to make up for Boley’s speed and leadership.

“We’ll make some adjustments because that’s where experience pays off,” Fewell said. “We’ll make some changes so that hopefully we can eliminate or reduce some of those errors (of last week) so they won’t occur.”

The three-safety alignment of Kenny Phillips, Antrel Rolle, and Deon Grant may go a long way in controlling the Eagles’ passing game behind Vince Young, who is expected to sit in while Michael Vick’s cracked ribs heal. Vick is listed as questionable, but not expected to play.

Boley’s spot at linebacker, a key position in the Giants’ effort to contain the NFL’s second-leading rusher, LeSean McCoy, will have to be manned by a rookie. It could be inspirational cancer survivor Mark Herzlich; last week’s fill-in, Spencer Paysinger; or on straight passing downs, sixth-rounder Jacquian Williams.

“They got to grow up,” Boley said.

Paysinger is the most advanced of the three in Boley’s spot on the weak side, having taken 20 snaps last week. Herzlich, a smart player coach Tom Coughlin said can get the players lined up properly, has yet to appear in the defense, but has been outstanding on special teams. And Williams has been seen mostly in passing situations as a rusher and cover man in the middle.

To speed the growing process, the undrafted Paysinger said the rookies have been practicing all three linebacker positions this week, though it’s likely Herzlich will get the start next to strong side linebacker Mathias Kiwanuka.

“You might see different combinations,” Paysinger said. “You might see me and Kiwi together, or you might see Mark and me, you might see Jacquian and me. We’ll have the ability to change it up, but right now not everything is settled.”

If Vick sits, the rookies will have to deal with a bigger and stronger version of him in Young. The former Titans starter beat the Giants in 2006 and 2010, most recently on a 10-of-16, 118-yard, one-touchdown performance.

“He won’t change their offense,” Coughlin said. “They’ll continue to feature the quarterback in various ways; move him around, scramble, he’s got a big arm. He’ll allow them to play their offense.”

McCoy will present the biggest problem. With 907 yards rushing and 10 touchdowns, he has the ability to tear up the league’s 20th-ranked run defense, a unit that has allowed as many touchdowns rushing (10) as passing.

The undrafted Herzlich could finally get his chance against McCoy and Young after a season of waiting to break into the defensive alignment.

“This is what I’ve been waiting all my life for, just a chance,” Herzlich said. “The biggest thing to keep in mind is to just stay poised and play football. You just got to make plays, run to the ball, and tackle them.”

Herzlich, at 6-foot-4, 246 pounds, has impressed Fewell with his first-team work this week.

“He’s a big man and he’s physical,” Fewell said. “Mark’s a go-getter. He’s one of those 100 percent guys that if he sees something, he’s going to go smack it and ask questions later.”

Gettting thrown into the fire against the league’s third best offense will be a huge challenge for the rookies.

“We’re more than ready,” Paysinger said.

NOTES: DE Justin Tuck (neck/groin) is questionable after spending Thursday’s practice on the stationary bike with a slight ankle sprain. “He got stepped on and the ankle rolled in practice (Wednesday),” coach Tom Coughlin said. “Hopefully it’s not a big deal. There’s a lot of soreness but no swelling.” Tuck said he expects to play Sunday. “It’s fine,” he said. “No swelling, no nothing.”.CB Prince Amukamara (foot) is also questionable, but could well make his NFL debut in the nickel defense.Starting LT Will Beatty (back) returned to practice after missing Thursday’s workout and is probable.RB Ahmad Bradshaw (foot) did not practice and is out for Sunday.

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