New York denied New England a place in the history books after the Giants overcame the Patriots 17-14 to win a dramatic Super Bowl XLII.
New England were attempting to emulate the 1972 Miami Dolphins in completing a perfect season but were dramatically edged out by the unfancied Giants at University of Phoenix Stadium in Glendale, Arizona.
Trailing for most of the game, Eli Manning proved the hero for New York as the quarterback engineered a 12-play, 83-yard drive late in the fourth quarter before hitting wide receiver Plaxico Burress in the end zone with just 35 seconds left for the winning touchdown.
The Giants put the first points on the board after Lawrence Tynes kicked a 32-yard field goal but New England took the lead on Laurence Maroney's one-yard run at the start of the second quarter after Giants linebacker Antonio Pearce was called for pass interference on Ben Watson in the end zone.
The Giants edged ahead 10-7 early in the fourth quarter when Manning found David Tyree with a five-yard pass over the middle after a play action.
But the Patriots hit back when Tom Brady connected with Randy Moss for a six-yard touchdown with just under three minutes to play when the wide receiver found himself all alone in the end zone.
However, Manning then marched the Giants down the field before locating a wide-open Burress to seal an unlikely victory at the death.
Manning, who was named the game's Most Valuable Player, admitted the scale of the Giants' triumph had yet to sink in as the quarterback followed in brother Peyton's footsteps last year in capturing a Super Bowl ring.
"The guys on this team and the run we've made, it's hard to believe - it really is," he said.
"We had a great fight and the defence played outstanding. It was just a great catch by David Tyree. I found a way to get loose and just really threw it up. He made an unbelievable catch and saved the game."
Burress added: "This is the greatest feeling in professional sports.
"For us to come out here and win a world championship tonight - nobody gave us a shot. Them guys (the defence) were out there playing phenomenal. We just hung in there and kept executing, we never got down on ourselves."