The Giants were not unbeaten, but they were playing at a far higher level than any other team in the NFL.

Since last year's postseason run, they had gone 15-1, including that stunning Super Bowl XLII victory in the Arizona desert over the unbeaten New England Patriots. Any thought that the Giants' unlikely ride to an NFL title was a fluke had been erased by their continued dominance through the first three-quarters of this season.

And then the Eagles showed up at Giants Stadium on Dec. 7 and beat the league's best team at its own game on a cold, blustery day. The Eagles' ability to run the Football and control the clock allowed them to leave East Rutherford, N.J., with a 20-14 victory.

Few people thought the Eagles could win that game at the Meadowlands, let alone be a Super Bowl contender this season. Coach Andy Reid's team was just two weeks removed from the infamous Donovan McNabb benching in the second half of a brutal road beating by the Baltimore Ravens.

Reid had already been fired by columnists in both the city's newspapers and thoughts of Jim Mora's sarcastic 1990s "Playoffs?" rant were dancing in the heads of Eagles fans.

Today's reality, of course, is that the Eagles are going back to Giants Stadium Sunday as the hottest team still standing in the NFC playoffs. They have won five of six games. Four of those five wins came against teams with winning records and two of them came against teams that are among the league's final eight.

It was fascinating to read some quotes from the Giants' players yesterday as they prepared for their third meeting of the season with the Eagles. The Giants are the 12-4 team with the top seed in the NFC, but they want to distance themselves from what happened in the regular season.

"The 2008 regular season is over with," Giants middle linebacker Antonio Pierce told the New York media on Monday. "There's nothing we can do about it. It's nothing that can help us moving forward. Come 1 o'clock Sunday, it's a totally different ball game."

The Giants' hope is that their December fade - they lost three of their final four games - does not continue into January.

It is the Eagles who had the December to remember even though it included a loss at Washington that almost cost them this chance at a rematch with the Giants.

It's also fascinating to look at the before-and-after December numbers posted by the Giants.

Before the Giants were dominated by the Eagles in a game that wasn't as close as the score indicated, they had the league's fourth-ranked offense and third-ranked defense. They were averaging 370.8 yards and a league-leading 29.3 points per game. Defensively, they were allowing just 279.1 yards and 17.2 points per game.

Eli Manning through 12 games was the NFL's seventh-rated passer with a 91.3 rating and well ahead of the Eagles' Donovan McNabb in almost every statistical category. The Giants' running trio of Brandon Jacobs, Derrick Ward and Ahmad Bradshaw seemed unstoppable.

A month later, the Giants don't look nearly as fierce, and the Eagles are being described as the NFC's most dangerous team.

New York averaged only 18.8 points in its final four games and allowed 22 per game. You can argue that the Giants didn't play their starters for much of the game in their regular-season finale against Minnesota, but even if you remove that game, their scoring statistics for December remain almost identical. In their last four games, the Giants averaged nearly 59 fewer yards on offense and allowed 51 more yards per game on defense than they had through their first 12 games.

Manning in the final month completed just 43.5 percent of his passes and had as many touchdowns (two) as interceptions. His December passer rating was 60.5. Jacobs, meanwhile, suffered a knee injury in the third quarter of the Eagles' win at Giants Stadium and missed two of the last three games.

The Giants, of course, also played the final month without wide receiver Plaxico Burress, whose season ended when he accidentally shot himself in the leg at a Manhattan nightclub in late November. Manning threw for 300 yards in a win at Washington the day after the Burress incident and it appeared as if the Giants would not miss their star receiver at all. In the four games since, however, the Giants' passing game has accumulated more than 200 yards just once.

Although the Giants didn't play their best in December, they did win the one game they needed to win, beating the Carolina Panthers in Week 16 to clinch the home-field advantage in the playoffs. It should also be noted that when the Eagles went to the Meadowlands last month, they were the more rested team after playing Arizona on Thanksgiving night. This time, it's the Giants with the extra rest after earning a first-round playoff bye.

It's no secret to the Giants that the Eagles are coming in as a hot team.

"Philadelphia has played very well, very good Football," Giants coach Tom Coughlin said Monday. "They are taking good care of the ball. Their defense has been very stingy."

The Eagles' hot December actually started with their final game in November, a 48-20 rout of Arizona.

McNabb was the league's 20th-rated passer (81.1) after his benching in Baltimore and was responsible for eight turnovers in a three-game stretch during which the Eagles went 0-2-1. During the Eagles' current 5-1 streak, McNabb has thrown for 10 touchdowns and suffered just two interceptions. He also has a 64.9 percent completion percentage and a 97.7 passer rating.

But the even bigger December story for the Eagles has been the defense, which has allowed an average of 10.8 points per game. The Eagles' defense has scored as many touchdowns (four) as it has allowed in the team's last five games.

A month ago this morning, a playoff rematch between the Eagles and Giants with a berth in the NFC championship at stake seemed about as likely as Andy Reid's winning a popularity contest in Philadelphia. To think that the Eagles would have a chance at winning that game was unimaginable.

Cellar Dweller to Wild Card

NFC East Standings Dec. 1 Dec. 29

1. Giants 11-1 1. Giants 12-4

2. Cowboys 8-4 2. Eagles 9-6-1

3. Redskins 7-5 3. Cowboys 9-7

4. Eagles 6-5-1 4. Redskins 8-8

Contact staff writer Bob Brookover

at 215-854-2577 or bbrookover@phillynews.com.