As he swerved into the end zone carrying an improbable game-sealing touchdown catch, Giants receiver Ike Hilliard held the ball aloft in his right hand and allowed himself a smile as he cupped his left hand to his ear. Around him, the once-thunderous Metrodome crowd had fallen into stunned silence. In seconds, the aisles seemed to be leaking grape juice, as purple-clad fans streamed soundlessly to the exits.

Hilliard's catch, for a 14-yard touchdown with 3 minutes 39 seconds left, struck the final blow in a 29-17 Giants victory over the previously undefeated Minnesota Vikings on Sunday. A bit later, the din moved into the Giants' locker room, where Hilliard joined the merriment even though his knee had swollen to nearly twice its size.

"Man, I'm glad we got a win," Hilliard said, easing himself onto a stool. "But it hurts."

The victory eased a lot of the Giants' ailments. Their battered special teams finally caught a break, turning a blocked punt into a wild, crucial first down. Their offense rallied behind a thin offensive line, firing off big plays at crucial moments even while one of the starters, guard Wayne Lucier, battled a 102-degree fever. The defense rose up in the second half and cut off the Vikings' big-play combination of Daunte Culpepper to Randy Moss. The secondary received an improbable lift from a rookie cornerback, Frank Walker, whose first N.F.L. interception set up Hilliard's score.

A 3-4 record never felt quite so good.

"Every win is something to build on," Giants left tackle Luke Petitgout said. "You come in here and beat the Vikings at home when you're 2-4. If that's not a building block, there is no such thing."

For a while, the game was going true to the Giants' unimpressive form. They were moving the ball at will down the field, but the Vikings intercepted a pass by Kerry Collins in the end zone to squelch one drive, and the Giants settled for field goals on three other drives. That left them holding a vulnerable 16-10 lead midway through the third quarter.

When the Vikings erased that — capping a 47-yard drive with a 1-yard touchdown pass from Culpepper to Moss with 6:22 left in the third — the Giants seemed to set the stage for another disappointment.

That was when the Giants found some luck. Or made some luck, depending on your point of view.

Forced to punt at their 12, the Giants watched in horror as Vikings safety Jack Brewer blew past the Giants' Wes Mallard and blocked Jeff Feagles's punt. The ball lay at the 1-yard line, right in front of Mallard. He picked it up and ran 13 yards for a first down with 13:54 left in the fourth quarter.

The Giants eventually punted, but it took an almost sure touchdown away from the Vikings (6-1).

"We got a break and we were very lucky," Collins said. "I'm not going to apologize for being lucky because we've been unlucky a lot lately. It was a break that went our way."

The defense stifled the Vikings' next drive, thanks to consecutive sacks of Culpepper by defensive end Michael Strahan. Collins then threw a 46-yard pass to tight end Jeremy Shockey, who was otherwise kept in check but was left in to help the offensive line block most of the day. Shockey caught the pass about 15 yards downfield, bulled through two tackles and took special care to wrap up the ball as he was finally tackled at the Vikings' 22.

"It's a play that works some of the time, and we were blessed to have everybody bite up on it," Shockey said. "I had no idea where I was. I just saw there was a clear lane ahead."

A penalty on that play for roughing the passer put the ball on the Vikings' 11, and running back Tiki Barber eventually scored from the 2 to give the Giants a 22-17 lead. But there was still 5:29 left, plenty of time for a Vikings comeback.

That comeback lasted exactly one play. Walker, who was inactive for the first five games of the season and forced into service only because of the season-threatening injury to cornerback Will Peterson, stepped in front of a pass intended for the rookie receiver Keenan Howry. Walker won the battle of rookies, snaring the pass and returning it to the Vikings' 17. Hilliard's touchdown 1:36 later was the final straw.

The offensive line survived the return of right tackle Ian Allen after he was benched one game into the season. It was also playing with two rookie starters, and nearly everyone shuffled into new spots. Lucier moved from center to left guard, which was nothing compared with the challenge of playing sick.

"Wayne had 102 fever; what else could go wrong?" Petitgout said. "He did a great job. We all hung in there."

Collins was sacked only once in 39 pass attempts. He completed 23 of them for 375 yards. The running game was not overwhelming, with 83 yards, but it made key first downs.

The special teams came into this game in such a funk that Nick Griesen, a linebacker who plays almost exclusively on special teams, got up and spoke in the locker room before the game. He urged the special teams to take pride in their work and tolerate no more mistakes. It worked. The blocked punt was terrible, but Mallard saved the play.

The defense also got a lift. With the veteran corner Will Allen drawing the task of covering Moss, the N.F.L.'s leading receiver, and Peterson reduced to injured spectator, the secondary could have folded. The other side of the field was left to nickel back Ralph Brown and Walker, who saw his first action last week, and it was limited. "We were in desperate need of another defensive back going out there and making a play," Allen said.

Walker was not the likeliest candidate. A sixth-round pick out of Tuskegee, he dislocated an elbow in the preseason and was a long shot to play at all this season.

He came off the field after an early series and ran over to Allen. "He came out the first time and said, `You ain't lyin', it's fast out there, way faster than I expected,' " Allen said. "He's cool. He's a good kid."

Across the Giants' locker room, Hilliard was alternately smiling and wincing. He had played through as much as anybody, having his knee driven into the unforgiving Metrodome turf in the first quarter. He would not hear of sitting out. He caught two touchdown passes and dropped a 2-point conversion pass, but he erased the drop with the game-sealing catch.

"You really can't say enough good things about him," Collins said. "The touchdown, it really wasn't a good throw. That was pretty much all Ike. He did a great job beating the guy. He's slippery, he's smart and he's great with the ball after the catch."

And he had the last laugh in a crowd he helped silence.