Carr returned an interception 49 yards for the clinching touchdown, and the Cowboys overcame a big night from Manning to beat him for the first time at their fancy $1.2 billion stadium in a 36-31 victory Sunday night.
Manning threw three touchdown passes to Victor Cruz and four overall, and he had New York in position for a comeback victory despite the flurry of mistakes.
But with the Giants trailing 30-24, Manning's pass went off the hand of running back De'Rel Scott into Carr's arms.
The cornerback beat Manning down the sideline with 1:50 left for Dallas' second defensive touchdown. Barry Church returned a fumble 27 yards for a touchdown in the third quarter.
The Cowboys had only 16 turnovers all last year, switched to a four-man front with new defensive coordinator Monte Kiffin and swore all preseason that taking the ball away was the foremost thing on their minds. They proved it from the first snap of the season.
It matched the most turnovers for the Giants since 1987, when they had seven against New Orleans. And it was the most Dallas has forced since 2003.
"I just think it's pretty exciting to see what our team defensively has been able to do here, in training camp, preseason and into the season," Romo said.
New York got the ball back, but the Cowboys forced a quick punt. After Dallas again failed to move the ball, Carr came through with the clinching interception.
Romo threw a 15-yard TD pass to Witten before halftime, and Dan Bailey also had two field goals (30 and 38 yards) by then for a 13-10 lead.
Cowboys owner Jerry Jones said Romo didn't receive any treatment, and that the medical staff cleared him to play. "One tough player, one tough man," Jones said. "He will go out and play in pain and play hurt."
NOTES: The crowd of 85,348 was significantly smaller than the NFL regular-season record crowd of 105,121 that watched the first Giants game at the stadium in its 2009 debut. ... Giants CB Prince Amukamara was knocked out of the game with a concussion after a helmet-on-helmet collision with S Ryan Mundy, who was cleared to return.
Copyright 2013 by The Associated Press