PHILADELPHIA (973espn.com) — In the NFL you always want your best players on the field but the attrition of this game is perhaps the lone constant in every city.

Eagles Pro Bowl tight end Zach Ertz explained that earlier in training camp.

"The injury rate is this game is 100 percent," Ertz said. "If you play long enough, you are going to get hurt."

For Kamu Grugier-Hill that reality hit home on Friday when the veteran linebacker clutched his left knee after making a tackle of Jordan Howard during a live session. The result could have been worse but a Grade 3 MCL sprain means the likely starter next to Nigel Bradham in the nickel defense will be sidelined for six to eight weeks, meaning regular-season games will be missed.

For Jim Schwartz, the goal becomes persevering until he has Grugier-Hill back in the lineup, a player who has been spectacular through the first eight practices of the summer.

"It hurts to lose Kamu just even for the little bit of time that we'll miss him because he was having a good camp," Schwartz said making note of the fact KGH has intercepted Carson Wentz twice during 7-on-7 drills during camp and had a knock down on a blitz in goal-line work in a live session on Saturday. "He was one of those guys we talked about a couple days ago that it’s his third year in the scheme - really fourth year - but third training camp, and really developing and showing a mastery of what we're doing.

"It's a little bit of a setback for him and us."

Schwartz has made mention in the past of the silver lining that came from all the injuries in the secondary last season. While it was ugly at times, throwing young players like Rasul Douglas and Avonte Maddox into the fire has resulted in much more self-assured options this time around.

"Short-term cost of having injured guys or having injured guys out and playing inexperienced guys, there are some start-up costs to that," Schwartz explained. "But once you make it past that you're able to gain from their experience."

In this case, the glass-is-half-full approach centers on Nate Gerry, who has already been getting first-team reps next to KGH as Bradham continues to work his way back from offseason toe surgery.

"We won some important games down the stretch last year with Nate Gerry as a starting linebacker for us," Schwartz said. "So we're certainly confident putting him in games, and he has confidence in himself. One thing about him is you know he'll be ready."

Bradham was the only proven option coming into the summer but his best role is not necessarily the Mike in the nickel which he would have been scheduled to play if the path forward was him next to Grugier-Hill.

“We know what Nigel Bradham brings to our organization,” LB coach Ken Flajole said. “He’s been a very productive guy. He’s filled in for Jordan [Hicks] when Jordan was hurt in the previous two years, so we know Nigel can slip in there [to middle linebacker]. I don’t know if that’s his most natural position but it may be the best thing for our football team. We’ll just have to see.”

Flajole's words regarding Bradham and the Mike role not being his "most natural position" could foreshadow a more natural fit with Gerry, a former safety at Nebraska who has handled the MLB role for the first-team throughout the spring and summer, sliding into the communication role.

"Nate's never going to be a 250-pound guy but Nate, without a doubt, is probably the brightest guy," Flajole explained. "He's smarter than I am in the meeting room. He gets it. When you've got a back-end perspective, particularly when it comes to the coverage part of it, I think it gives you a unique perspective because all of a sudden, he's the one guy that understands how everything fits together with the back end."

Schwartz seems to agree.

"We haven't paid that much of a price for [Nate] being on the field," the DC said. "He's helped us win. He's made some big plays. Like I said, he was a key part of the winning those games down the stretch that was able to get us to the playoffs."

-John McMullen covers the Eagles and the NFL for 973espn.com. You can reach him at jmcmullen44@gmail.com or on Twitter @JFMcMullen

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