For the second consecutive week, the Eagles lost a divisional game at home in which the defense held up its end of the bargain and the offense failed to reach the end zone. The other common denominator between last week's loss to the Dallas Cowboys Sunday's 15-7 loss to the New York Giants? For the second straight game, rookie fourth-round pick Matt Barkley was forced into action after the Eagles' starting quarterback was injured during an ineffective day's work.

Last week, Nick Foles suffered a concussion after three quarters of unimpressive passing. With Foles out this week, Michael Vick returned to action on the heels of a hamstring injury that had kept him out of action since he suffered the injury against the Giants three weeks ago. Over four drives that spanned two quarters, Vick was six-of-nine for 31 yards and one interception. After reinjuring his ailing hamstring, Vick was pulled from the game in favor of Barkley and though the rookie acquitted himself reasonably – he completed 17-of-26 passes for 158 yards, no touchdowns, one end-of-game interception and a costly lost fumble – the high-octane offense of the early part of the season was nowhere to be found.

"I think we've had some instability at the quarterback position," said head coach Chip Kelly after the game. "I think we've also got to step up. And it starts with me. I'm the play-caller. I'm the guy calling plays. In the last two weeks, I haven't done a very good job of it. Until we can get that straightened out, the disappointing thing is I think our defense played a really, really good football game again today. They've really come along. But offensively we haven't done what we need to do to win two football games and we need to get that fixed."

Now, at 3-5 with a cross-country trip to Oakland on the horizon, Kelly and the Eagles find themselves mired in uncertainty at the most important position in the game.

"I think when you're unsettled at that position in this league, it's real difficult," Kelly said. "You didn't have a concrete answer. I know some of you wanted it during the week – is he going to start? – on Tuesday. I don't know if he's starting on Tuesday. How do we go through the week of practice and see where he is? And that was the way it was. I was telling the truth then. I was concerned all week long. When you're not settled at that position in this league, you better have a quarterback. And right now we're unstable at the quarterback spot and we are not playing well at the quarterback spot, and we lost our last two games because of it."

So with Vick and Foles on the mend, the question at quarterback becomes: now what? Vick, it seems, will need to take it slowly moving forward.

"Yeah I'm concerned," Kelly said of Vick. "I know we thought it was going to be a 10-to-14-day thing and so did Mike. And Mike felt great. This is the one thing that's disappointing for Mike. He did everything from a rehab standpoint that we asked him to do. And put in all the time. And not to be able to go out there and be a hundred percent is a concern, yes."

And Foles?

"I know he was in on Saturday, but he still hasn't been cleared to fully practice," Kelly said. "So that's a big question mark going into next week. Again, until he gets fully cleared, he has to also see an independent, so he can't participate in anything. So he was in, he attended meetings on Saturday, and he was around. But he has not been cleared to play yet."

All of which brings it back to the rookie who has been forced into relief each of the past two weeks. Perhaps this week Barkley will get a chance to play with the first-team offense throughout the week of practice.

"I really don't know right now," Kelly said. "It really depends on the full report on Mike and the full report on Nick. But it could look that way."

Meanwhile, over the course of eight games, the identity of the Eagles has flipped. At the start of the season, the expectation was that the productive, up-tempo Eagles offense would carry the team while the defense adjusted to its new scheme and personnel. Now, after two straight impressive weeks, the Eagles defense has become the more reliable of the two units.

"I just think they're starting to really get the grasp and understanding of what our defensive coaches are doing," Kelly said of the defense. "I think they're in the right spots. They're holding disguises a little bit longer. They can confuse the quarterback at times … They're starting to understand the package. I think since day one they're playing with great effort and doing a better job tackling right now. I think we defended some of the deep balls, some of the balls thrown in the end zone. They've done a really good job with that. They haven't gotten the ball thrown over their head, and they've kept the ball in front of them. So I think we can build where we are on the defensive side."

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