YOU CAN TALK about that huge late failure to convert on fourth-and-1, and a couple of crucial replay challenges that didn't go the Eagles' way, and a hobbled Brian Westbrook, but none of that was the biggest reason the Birds lost their last meeting with the Giants, 36-31, on Nov. 9 at Lincoln Financial Field.

The essence of the game was the Giants' offensive line controlling the line of scrimmage, outplaying the Eagles' defenders. New York ran for 219 yards on 45 carries, and controlled the ball for 39 minutes and 10 seconds, leaving the Birds with only 20:50 worth of offense. That was why some observers felt the game really wasn't as close as the final score.

And that's the equation that will have to change if the 6-5-1 Eagles are to upset the 11-1 Giants on Sunday at the Meadowlands.

Weapons come and weapons go - Plaxico Burress is gone, you probably have heard. Brandon Jacobs, who romped through the Birds for 126 yards and two touchdowns on 22 carries, missed the Giants' win over Arizona 2 weeks back because of a knee injury and was held to 71 yards on 21 carries last week by the Redskins. But whatever the Giants have going, their seamless, unflappable offensive line seems to be able to make it work, as the fulcrum of the NFL's highest-scoring offense.

"They've all played together for 4 years now. They know each other. It's amazing how they've been injury-free - they hardly ever miss a game," Eagles defensive coordinator Jim Johnson said yesterday. "That's what you'd like to have in an offensive line, that experience . . . the more you see, especially playing under the same system for years - they see stunts, they see blitzes, and they just do a great job."

They are left tackle David Diehl, left guard Rich Seubert, center Shaun O'Hara, right guard Chris Snee and right tackle Kareem McKenzie. The highest draft pick among them was Snee, whom Johnson said he considers as good a guard as there is in the league right now; Snee was a second-round choice, 34th overall, by the Giants in 2004. Diehl, originally a guard, was a fifth-round pick in 2003. Seubert arrived as an undrafted rookie in 2001. O'Hara, originally an undrafted find of the Browns, signed with New York as a free agent in 2004. McKenzie arrived the same way, the same year, having originally been a third-round pick of the Jets.

They aren't the league's most physically imposing group and they haven't dominated Pro Bowl discussions over the years; in fact, none of them has ever been picked for Hawaii. But right now they are the best offensive line in football.

"It's just a bunch of guys that work very well together," said Eagles reserve linebacker Tank Daniels, who practiced against the Giants' offensive line last season, when he played for the Super Bowl champs. "That line's not concerned about the Pro Bowl or money or this and that - those guys are just, 'Let's go out and do what we have to do to win the game.' If it's run block, pass block, whatever . . . nobody's into individual goals. That goes a long way, I think."

Eagles defensive tackle Brodrick Bunkley said: "It's a great group. It seems like the timing is perfect, when the back hits the hole. They're smart and they work well together."

Also, "they play nasty," strong safety Quintin Mikell observed.

All that said, the Eagles feel they can do a better job than they did last month. Johnson and his players indicated they were a little surprised at some of the things the Giants did in the run game - Johnson particularly mentioned how effectively tight end Kevin Boss blocked his defensive ends as something he hadn't anticipated. (Eagles fans reading this, feel free to grind your teeth, though in the interest of your dental health, we're omitting the quotes from Johnson about how the Giants' tight end and their fullback - Madison Hedgecock - are such valuable assets to their running game. Yeah, that's just the way it is here, too, right?)

"We're going to find out," Johnson said, when asked if his group was better equipped for the challenge this time. "We better. It's as simple as that, we better. I think our guys have a lot more respect for the Giants' running game than before we went against them; we really do . . . I think they're more up to the matchup, as far as going up against Boss. I think we were a little surprised by how they ran the ball and I think our team will respond to that."

Mikell said: "They changed up a couple little things here and there, but ultimately we've just got to execute. We didn't come out there and play the way we needed to and set the edge, we didn't make tackles when we needed to."

The Eagles' defense has changed a little in the last month. Akeem Jordan is more athletic at weakside linebacker than Omar Gaither was. Defensive ends Chris Clemons and Victor Abiamiri are factoring more into Johnson's rotation, as is rookie defensive tackle Trevor Laws. The Giants will see more of tough little Joselio Hanson at nickel corner, less of Lito Sheppard.

Johnson second-guessed himself after last month's game, wondering if he'd worried too much about longtime Bird-killer Burress and too little about the run. He was asked yesterday if Burress' absence makes it easier to bring a safety up into the box for run defense.

"It does," he said. "There will be times that it does, but you still have to be smart. That's what the Redskins did last week, they put eight in the box every play and [Eli Manning] threw for 300 yards almost in the first half. There's a happy medium, you know? We've got to mix it up a little bit. There are going to be times where we're going to have to keep an extra guy in the box to stop the run, but also we have to play coverage on these receivers, too." *

For more Eagles coverage and opinion, read the Daily News' Eagles blog, Eagletarian, at www.eagletarian.com