It has happened twice in December, the TV cameras catching Donovan McNabb on the sideline with a facial expression that says more than the veteran quarterback is normally willing to reveal.

Three weeks ago in the Meadowlands, after the Giants scored to erase the Eagles' lead, McNabb wore a mask of pained frustration, a what-more-do-we-have-to-do look of dismay.

Then he went out and threw that long touchdown pass to DeSean Jackson, giving the Eagles the lead for good.

On Sunday, the camera found McNabb kneeling on the sideline as David Akers' game-winning field goal sailed through the uprights. As his teammates and the coaches cheered, McNabb looked utterly exhausted and spent. Again, it had taken extraordinary efforts to win a game that had seemed won.

It is a heady time for the franchise QB, and things are about to get even more intense. McNabb is facing a month that could potentially be career-redefining - not to mention pretty darn strange.

Look around the NFC playoff field, which was set over the weekend. There are a couple of quarterbacks who are older than McNabb and have won rings: Brett Favre and Kurt Warner. There are a couple of quarterbacks who are younger and who bear fewer physical and emotional postseason scars: Drew Brees and Aaron Rodgers.

And there is one QB whose career stands as a sort of counterpoint to McNabb's. While No. 5 has won a bunch of postseason games, often with seriously flawed teams, No. 9 has put up great numbers, played with great talent around him and never won a single playoff game.

Fittingly, McNabb will go head-to-head with Tony Romo Sunday with a chance to earn a first-round bye - but also a real chance to meet again the very next week in a first-round playoff game. The Eagles' rivalry with the Cowboys has featured plenty of highs and too many lows, but the next two weeks could be an all-timer.

A lot of things can happen to decide the outcomes, including things that don't involve McNabb. But we all know that, in the end, McNabb will be on the hook. That's just how it goes for quarterbacks. It is the same for Romo, whose label of December choke artist is as firmly stuck on as McNabb's rep for losing in the biggest games. It is never completely fair or accurate to blame a single player, but that's part of the QB's job description.

Given their careers and the public pressures each man faces, it would be especially galling for McNabb to watch Romo surpass him on the way to a Super Bowl title. That happened once upon a time to Randall Cunningham, whose only playoff win as an Eagle was followed by a blowout loss to the burgeoning Troy Aikman-led Cowboys dynasty. And it happened to McNabb when Eli Manning was able to lead the Giants to a championship a couple of years ago.

Remember all that talk about the Hall of Fame a few months ago? McNabb's career numbers would look that much less impressive if he was the only NFC East QB of his era not to win a title.

So he has a terrific opportunity over the next two or three weeks to elbow Romo off the mountainside and elevate himself. Winning Sunday could mean everything or nothing, depending on what the Minnesota Vikings do. But whether it's Week 17 or Wild Card Weekend, McNabb and the Eagles should have their chance to cast Romo and the Cowboys into turmoil.

The alternative is just too much for any serious Eagles fan to stomach.

McNabb has played on better all-around teams than this current edition of the Eagles. But he has not played with more weapons, or against an NFC field this wide open. This year, of all the years, he is positioned to carry this team all the way. And it will take just that, since the Eagles' defense is a work-in-progress and the offense runs on the combustible fuel of youth.

If McNabb is to rebrand himself as a championship QB, it must be said that the campaign began within the locker room. The Eagles' rookies were in elementary school when McNabb began his NFL career. A few of his teammates, he said earlier this year, admitted they had played Madden video football as McNabb. In other words, they view him as an established superstar QB and, lately, he has been filling that role very nicely.

They will follow where he leads, and they are good enough to help him get where he wants to go. It is a rare combination.

McNabb knows the hardest part is yet to come. He also knows that he won't get many more chances as good as this. The pressure is on. You can see it all over his face.