METAIRIE — Every time New Orleans Saints interim coach Joe Vitt turns on game tape of the Philadelphia Eagles offense, he is haunted by the past and mindful of a daunting future facing the NFL’s worst defense.

The mere thought of trying to defend quarterback Michael Vick on Monday night at the Mercedes-Benz Superdome is causing sleepless nights for Vitt leading up to the prime-time battle on ESPN between two desperate teams in need of a victory.

The slumping Eagles (3-4) face the struggling Saints (2-5) on the eve of the presidential election.

Kickoff is 7:40 p.m.

“My biggest nightmare against Michael Vick was in 2004 in a playoff game when I was with the Rams,’’ Vitt said referring to a divisional round game between St. Louis and Atlanta on Jan. 15, 2005, when Vick starred for the Falcons. “That was my first exposure to him and he ran for 180 yards.’’

Vick played well for the Falcons in that 47-14 pasting of the Rams at the Georgia Dome, but not that well. A quick check of the NFL’s official game summary indicates Vick actually rushed for 119 yards on eight carries for a robust 14.9-yard average. Perhaps, it just seemed like 180 yards. Running circles around a defense sometimes has that effect.

Asked if the Rams used a “spy’’ defender against Vick, Vitt replied wryly: “We had a spy. The spy we had wasn’t as fast as him. It’s a game of matchups.”

Which brings us to Monday night’s game: Vick versus a Saints defense that has become a laughingstock of the NFL, yielding yards (474.4 per game ) and points (30.9 per game) at an alarming clip.

Question is, which Michael Vick will show up:

The good Michael Vick, the fleet-footed quarterback with a rocket arm and makes good decisions in the pocket, who can create a schematic nightmare for first-year Saints defensive coordinator Steve Spagnuolo.

Or the bad Michael Vick, the impatient, turnover-waiting-to-happen signal caller, who could be just the tonic for a sick Saints defense.

“Michael Vick is truly a gifted athlete,’’ Vitt said. “You better know where his launch point is. You better know where he likes to go on the field. If we let him escape to his left — to our right — and let him hold the ball, we’re going to get exactly what we deserve. There’s going to have to be a definite flush pattern with Michael to try to contain him.

“There are certain places on the field where you cannot let him get out,’’ Vitt said. “We call this the midpoint, from the hash to the numbers, in between that area is where we’d like to play this game. It’s a perimeter running game with a quick, fast, explosive backs that makes a lot of plays outside the numbers. This quarterback, if he gets outside that midpoint area, can ruin your party. There’s a certain way we have to do this. We have to have edge force, do the best job that we can of playing this thing inside the midpoint, shrinking these running lanes down and getting our hands up.’’

Monday night will mark the first time Vick has played against the Saints for a team other than the Falcons. In seven previous outings against New Orleans, all with Atlanta, Vick is 5-2, with both losses coming during coach Sean Payton’s rookie season in 2006.

In fact, Vick was under center for the Falcons on that emotionally charged night of Sept. 25, 2006, when the Superdome reopened after being shuttered the previous season because of horrific damage inflicted by Hurricane Katrina.

The Saints dominated Vick and the Falcons, winning handily 23-3.

Based on the seven previous encounters, the running Vick appears to present a bigger problem for the Saints defense than the passing Vick.

“You can’t simulate his speed,’’ Saints middle linebacker Curtis Lofton said. “You just got to do the best you can and know the angle that you take in practice isn’t going to be the angle that you take in the game.’’

“In a normal coverage, like in a ‘Cover 3’, you have the flat and the receiver in the flat,’’ Saints linebacker Scott Shanle said. “Against Michael, you don’t care about the flat receiver. You care about the boot; you care more about Michael Vick getting out on the perimeter. He makes you change up normal, everyday defenses to defend him.’’

Despite his shades of brilliance, Vick is in danger of losing his job. He is responsible for 13 giveaways — eight interceptions and five lost fumbles — and embattled Eagles’ Coach Andy Reid is considering inserting rookie quarterback Nick Foles under center.

In fact, it appears that Vick has come to the crossroads of his season.

A good performance Monday night likely would save his job at least for one more week. A dismal outing might grease his exit.

“I don’t listen to the talk,’’ Vitt said. “I look at the film. I’ve gone against Michael (Vick) enough. Michael has earned his stripes in this league based on what he’s done. I’ve got great respect for him.

“When Mike Vick came into the league, he’s the one that kind of rewrote the quarterback position and what you can do at the quarterback position. (With players like him), you’re defending a 12th player on the field and a sixth eligible receiver because that’s the kind of skill he has.”

The kind of skill set that leaves Vitt bleary eyed from lack of sleep.