Mike Celizic

We knew nobody was going to get through this season undefeated, not even the New York Giants. But what we didn’t know — but should have expected — was that they’d pick a team like the Cleveland Browns to lose their first game to.

The Giants have to be kicking themselves for neglecting to show up for a Monday Night in Cleveland. Just a day earlier, they had watched the Redskins and Cowboys both lose to fall to 4-2, and the defending champs knew that all they had to do was take care of business against one of the league’s bottom feeders and they’d have a comfy two-game bulge in the brutally tough NFC East.

That would have been a huge advantage, a down payment on a divisional title and another trip to the playoffs. And all Big Blue had to do to get it was go to Cleveland with malice in their hearts and passion in their play.

Instead, they walked into an ambush that anyone should have seen coming. They knew the Browns aren’t as bad as their 1-4 record suggested. They knew that Derek Anderson had a big arm and Braylon Edwards had big-play potential. They knew that the Browns, who hadn’t been featured on Monday Night in just short of forever, would be sky high for this game against a Giants team that had at one time been the Browns’ biggest rival.

And still, the Giants didn’t look ready.

Give Cleveland credit for doing almost everything right for a change. The Browns didn’t give up a sack, didn’t lose a fumble, didn’t throw an interception and — get this — didn’t punt. They controlled this game from start to finish and manhandled the best team in the NFL. And if they could only learn to count to “hut two” they’d have cut out a half dozen stupid penalties and really sent a message to the rest of the league.

But even with their lamentable penchant for procedure penalties, the Browns had no trouble exposing the weaknesses in what had looked like a juggernaut Giants’ team. And you can bet the rest of the NFL was taking notes as Anderson and Edwards exploited New York’s secondary and the Cleveland defensive front put constant pressure on Eli Manning.

What has to worry Giants fans was watching Manning face that pressure and revert to the quarterback he was before he and the Giants learned to win last year. After throwing just two interceptions in his first four games, Manning threw three to the brown jerseys Monday night.

One interception looked like a case of miscommunication with Plaxico Burress — the guy who doesn’t see why it’s important to come to all the meetings. The other two were just awful throws.

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Manning went down just once, but he’s like every other quarterback who’s ever played the game. Put a heavy rush on him, and he becomes ordinary.

It wasn’t just the Giants offense that failed to perform, though. The defense did more than its part. Coming into the game, the Giants were third in the league in total defense, allowing 236 yards a game. Cleveland was last in offense, at 210 yards per game. And few teams abused quarterbacks like the Giants do.

Apparently, the Giants defense missed the plane, because the outfit that showed up on the shores of Lake Erie gave up more 454 yards and didn’t sack Anderson once. The Browns quarterback had come into the game with three touchdowns and six interceptions and a completion percentage under 50 percent. He was one bad quarter away from seeing Brady Quinn take his place.

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With the Giants manufacturing zero pass rush, Anderson went 18-for-29 for 310 yards, two touchdowns and no picks.

The Giants will play better. Coach Tom Coughlin will see to that. And they’re still in good shape at 4-1 to make the playoffs so they can attempt to defend their title.

But they could have been 5-0 with a two-game lead in the NFC East. They could have added to their aura of invincibility. All they had to do was remember that there’s nothing more dangerous than a one-win team on a national stage in front of its home crowd.

But the Giants fell prey to their own press clippings. That doesn’t make them bad, just human. That’s no consolation to them today, nor should it be. They had a golden opportunity, and you can’t even say they let it slip through their fingers because they never even had it in their grasp.

The Giants didn’t show up. It’s that simple.

How much they will come to regret it — if at all — is up to them.

NFL game stories Quick look at Week 13 games TEXANS 30, JAGUARS 17: Slaton scores 2 TDs in easy win STEELERS 33, PATRIOTS 10: Defense shuts down New England GIANTS 23, REDSKINS 7: Manning throws for 305 yards for N.Y. (11-1) BRONCOS 34, JETS 17: Cutler shines in rout of New York COLTS 10, BROWNS 6: Indy (8-4) wins fifth straight game FALCONS 22, CHARGERS 16: Ex-Bolt Turner runs for 120 yards PANTHERS 35, PACKERS 31: Williams scores 4 TDs BUCS 23, SAINTS 20: Defense keeps Tampa atop NFC South RAVENS 34, BENGALS 3: Baltimore shows flash on offense, defense DOLPHINS 16, RAMS 12: Miami (7-5) stays in playoff hunt 49ERS 10, BILLS 3: S.F. first West Coast team to win in East this year COWBOYS 34, SEAHAWKS 9: Romo throws 3 TDs, Dallas (8-4) rolls EAGLES 48, CARDS 20: McNabb throws 4 TDs, delays Arizona's title TITANS 47, LIONS 10: Tennessee (11-1) runs wild vs. winless Detroit

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