EAST RUTHERFORD, N.J. - From any vantage point, the Eagles' defense looks impressive.

Jim Johnson, their brilliant coordinator, was forced to coach Sunday's 23-11 victory over the Giants from the press box because he is suffering from a bad back. But his defense continues to be a pain in the neck for opponents.

Defense has been the constant in the Eagles' improbable run to the NFC championship game against the Cardinals. The Eagles held the Giants without a touchdown Sunday. The Eagles held the Cowboys without a touchdown during Philadelphia's 44-6 victory in Week 17 that put the Eagles in the postseason.

The Ravens and Steelers have tremendous defenses that will meet for the AFC championship. But you can't spell Philadelphia without a D. And the mastermind of the Eagles' defense is Johnson.

"I'm partial, but I've got the best defensive coordinator in the National Football League," said Eagles coach Andy Reid after the game. "The guys believe in him and the things he does. For being almost 100 years old, he's kept it fresh."

Johnson is actually 67 and perfectly content in his role as Reid's right-hand man, a job he has held since 1999. Johnson has no interest in pursuing any of the NFL's current head coaching vacancies, and the Eagles are fortunate to have him. Give Johnson enough time to study an offense and he will find a way to stifle it.

This was Philadelphia's third game against the Giants this season, and it often looked like the Eagles were in the huddle with Eli Manning. The Eagles are known for blitzing and putting pressure on quarterbacks, and this was another example, as Manning threw two interceptions. But on Sunday, the Eagles also stoned the Giants' running game twice in crucial fourthand- 1 situations, deflating any chance the Giants had to rally.

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Hardly anyone saw this coming when the Eagles were struggling in November with a 5-5-1 record. But Johnson believed the Eagles were better than that. In the playoffs, they have been much better.

"I wish I could say that we were going to go to the playoffs a month or two ago," said Johnson. "I felt we were a good football team. For whatever reason, things weren't going our way. We struggled for a while. We kind of bounced back."

They bounced back in a big way. You could almost foresee Sunday's outcome by examining how both teams had played recently. The Giants had lost three of their last four regular-season games while the Eagles had won five of six.

The Giants sorely missed wide receiver Plaxico Burress Sunday. His height and ability make him almost impossible to cover one-on-one. Without him to worry about, the Eagles single-covered the Giants' wide receivers and moved their safeties closer to the line to stop the run.

"When he isn't there, there is a huge part of their offense taken away," said Eagles safety Brian Dawkins. "If he has a one-on-one, they feel he is going to win that battle nine times out of 10. You can't play Plaxico one-on-one without expecting him to have a huge game."

Now the Eagles face another huge game. The Cardinals' high-powered offense shredded the Panthers on Saturday, as wide receiver Larry Fitzgerald ran freely through the Carolina secondary. Fitzgerald is one of the game's elite receivers, able to make great catches even when he is covered. But expect Philadelphia's defense to offer more resistance than the Panthers did.

The Eagles have held their last six opponents to 14 points or fewer. Interestingly, the Cardinals were the last team to score more than 14 against the Eagles, but Philadelphia pummeled them, 48-20, on Thanksgiving night.

That game was in Philadelphia. Sunday's NFC championship will be in Arizona, and both teams have improved greatly since the earlier meeting.

But a much as people talk about Donovan McNabb and Brian Westbrook, the Eagles have become a Super Bowl threat because of their defense. Johnson is making the right calls, the players are making big plays, and the Eagles are playing their best football at the right time. For much of the season, they looked lost. Now they look dangerous.

"If you get hot at the right time, you are going to be dangerous in the playoffs,'' Westbrook said. "Everyone knows the cliche — defense wins you championships. Our defense is playing lights-out."

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