THEY ARE Forrest Gump's box of chocolates.

You never know what you're gonna git with the Eagles defense.

They made you feel like a million bucks on Thanksgiving and made you crazier than Lieutenant Dan amid a hurricane that Sunday afternoon in Green Bay.

They nearly stole a game for you in San Francisco earlier this season, nearly gave one away earlier this season against Washington.

They're a group that looks real good at times on the field and hardly ever on paper, a defense that leads the NFC in sacks with 42, a unit with a run defense that dares you to pass, then surrenders a whopping 24 touchdowns this season through the air.

And here's the most unnerving part: They will have to play as well or almost as well as the one across the field Sunday if the Eagles have any shot of beating the Seattle Seahawks.

"I don't think we go into it thinking we [the defense] have to win the game," Eagles safety Malcom Jenkins said yesterday. "But there's a difference in our offense going against any other defense and our offense going against Seattle. You do realize this is probably going to be a defensive struggle. We don't expect our offense to go in and put up 35 points on this defense. But we don't approach it any other way. There's nothing we've got to do extraordinary that we wouldn't want to go out and do anyway."

The Eagles defense is ranked 24th among 32 NFL teams this season, in a large part because of those big passing plays. They are 12th against the rush and 19th in the NFL in points allowed this season. They have played their best against stationary quarterbacks (Andrew Luck, Eli Manning) and injured mobile ones (Cam Newton, Tony Romo), looked awful against Aaron Rodgers in Green Bay only three games ago - but then again, what defense hasn't this season?

On their good weeks, they compare themselves to the best. On their worst weeks, they talk about missed assignments and games getting away from them.

They want to be considered among the league's best, and sometimes think they are.

"You must not have watched the Eagles defense," Fletcher Cox told me yesterday when I asked him about measuring up against the NFL's top brand name this Sunday at Lincoln Financial Field.

Ah, but I have. So have you. They are not the brand that is the Seahawks defense, a group that won last season's Super Bowl by making Peyton Manning look like, well, Eli Manning.

Or, well, Archie.

After pressing the snooze button for the early hours of this long season, Richard Sherman and the lads have been guzzling the coffee pot of late, allowing only a lone field goal each to Arizona and San Francisco - their two NFC West rivals - on successive weeks.

Just like that, Seattle has positioned itself to jockey for one of the NFC's two byes, with games against most of the other suitors still at hand - such as Sunday's showdown.

The Eagles? Well, we have justifiably celebrated the emergence of Cox as one of the NFL's best defensive ends, even as we twitch nervously over a secondary that ticks like an activated bomb during any mid- or long-range pass play. Do we trust what we saw against Dallas and at times against Tennessee as a continued evolution and improvement, or will that bomb detonate again the next time it plays against a healthy, top-notch mobile quarterback - such as, say, Russell Wilson?

You could almost hear the knuckles cracking throughout the Delaware Valley yesterday when Jenkins compared Wilson to Rodgers, because of his ability to see downfield amid a play-extending scramble, or when he spoke of late-releasing running backs and tight ends.

"Although they're both elite quarterbacks, there's a completely different offense coming at you," Eagles defensive coordinator Bill Davis said. "The people around them, the game and how the score - everything changes . . . When we faced Green Bay in Green Bay, the quarterback was absolutely on fire, and it takes nothing away from us. We had some tight coverage that he threw the ball in there on and that game separated on us, and, all of a sudden, it was different than the Dallas game, where we got a little bit of a lead."

Said Jenkins: "If we can keep the ball in front of us and get into a drop-back pass game . . . they can do it, but it's not what they do best. So we want to go at what they do best and see how we fare."

The upside of faring well would clearly translate into player and consumer confidence, maybe even give our knuckles and twitching a little relief.

Are they an improving brand, as their games against Tennessee and Dallas hint at?

Or are they that maddening box of chocolates: hard one bite, gooey and soft the next?

"If we're going to call ourselves a good defense, we've got to stop good guys," Brandon Graham said. "We know who we are. We've just got to go out there and be who we are."

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