IRVING, TEX., NOV. 2 -- Just a week ago, some of the New York Giants had promised victory over the Dallas Cowboys. A couple said it wouldn't even be close. The Giants knew they had a torturous road ahead and didn't plan on wasting any time disposing of the Cowboys.

But just when the Cowboys were beginning to look uncommonly shabby, they were able to come up with an upset at Texas Stadium tonight, beating the Giants, 33-24, and leaving the defending Super Bowl champions 1-6, desperate and wounded.

The Giants led by as many as 10 points in the fourth quarter, but fell apart in the final 12 minutes, committing four turnovers that led to 19 points for the Cowboys. Also, quarterback Phil Simms went down in a heap with sprained ligaments in his knee while throwing the second of two interceptions that led to the Cowboys' improbable comeback. The Giants' trainers said Simms' injury is not believed to be serious and he could play next week against New England.

It was the second time this season that a decidedly underdog Cowboys team defeated the union Giants. It was also the Cowboys' fifth win over the Giants in the last six meetings. There were so many Dallas heroes it's difficult to keep track.

Ed (Too Tall) Jones had four of Dallas' seven sacks and tipped two passes that were intercepted, and kicker Roger Ruzek had four field goals in the fourth quarter.

The last of those four, a 35-yarder with 46 seconds left, put the Giants away for good and kept the Cowboys (4-3) in the chase for a wild-card playoff berth in the National Football Conference.

It also gave the Cowboys a much-needed boost in self-respect, having been embarrassed by the Eagles last week and threatened by half the teams in the league for the behavior (or perceived) behavior of club officials and players during the players' strike.

Tony Dorsett said the Cowboys decided during team meetings to "bury the hatchet and just play. The vibes were good and we fought like the dickens, even when it looked bleak. We were fed up with teams saying they're going to kick our butts. If you beat us, we're going to make you sore as hell."

The mood in the Dallas dressing room was jubilant, almost defiant, a rarity for a franchise where winning is expected.

But that was because the Cowboys beat the Giants in every way imaginable when that just didn't seem possible. Dallas used a basic four-man rush to batter that Giants. New York guard Billy Ard said he felt like "Tyrell Biggs trying to keep Mike Tyson off of you in the final round."

The Dallas offense survived, and the defense dominated the game. Randy White, the old all-pro, said, "this felt like the old days."

And Dorsett added, "Doomsday was back. We couldn't have won the game without them."

Meanwhile, the Giants were groping for explanations. How, when they were desperate for a victory, could the offensive line let Simms get injured, let him and Jeff Rutledge get sacked seven times, let a bunch of over-the-hill Cowboys look like the Bears?

"They're a decent front four, but there's no way that should happen," Ard said. "They're not the Bears, after all."

No, but the result was the same.

After Simms threw his second touchdown pass of the game, a 33-yarder to Lionel Emanuel to put the Giants ahead, 24-14, on the first play of the fourth quarter, the game seemed over.

But Ruzek kicked a 34-yard field goal with 12 minutes left to make it 24-17. And only two minutes later, Jones tipped a Simms pass that Jim Jeffcoat intercepted and returned 26 yards for the touchdown that tied the game, 24-24.

The Giants were forced to punt on the next series, and the Cowboys got another field goal out of Ruzek, this one a 49-yarder that put the Cowboys up, 27-24, with 4:11 to play.

So much more would happen. Lee Rouson fumbled the ensuing kickoff and Ruzek kicked a 40-yarder for a 30-24 lead with 2:54 left.

Jones batted another Simms pass while Jeffcoat was knocking him out of the game. The ball, meanwhile, landed in the hands of Randy White for his first career interception. Herschel Walker fumbled, but the Cowboys got the ball right back when Jones sacked Rutledge, whose fumble was recovered by Jeffcoat. One more field goal by Ruzek and the game was over.

The Giants, of course, were left to ponder the playoffs. Oh, many of them talked about taking it a week at a time. But the Giants don't want to get to the point where they're playing out the string.

"It'll be difficult now," Coach Bill Parcells said. "We'll need some help, but things change in this league awfully fast. We'll see."

Center Bart Oates, one of the Giants who had bodaciously guaranteed victory, said somberly, "Yes, I said it. I was wrong. I guess I'm going to get out of the predicting business. But I felt strongly.

"What did we have, four turnovers? You can't self-destruct any more than we did in the fourth quarter. I guess we'll go back and have some self-pity tonight. But we've got to have some resolve. Real fast."