NFL

Giants survive scare from Dolphins

HEADS UP: Corey Webster (right) celebrates with Aaron Ross after Webster’s game-sealing interception in the final two minutes. (Reuters)

VICTOR-Y IN BLUE: Victor Cruz spins away from Will Allen on his way to a 25-yard, game-winning touchdown catch in the Giants’ 20-17 win over the winless Dolphins. (Getty Images)

Osi Umenyiora was hanging around the X-ray room after the Giants had just barely disposed of the winless Dolphins when he saw that the Rams had broken out of the winless column by upsetting the Saints.

“So you never know what’s going to happen,” Umenyiora said. “There’s no such thing about playing down or playing up. You win by one or you win by 20, you win.”

For the better part of three hours yesterday, the winning part was somehow escaping the Giants, who were hearing it from the crowd of 79,302 for repeated blunders and for keeping the Dolphins not only in the game but ahead. A 7-0 deficit became a 14-3 deficit and the Giants still trailed 17-10 heading into the fourth quarter. It was the day before Halloween and the home team was scaring the heck out of its paying customers.

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“You go out and start a little flat and let them get some energy and this is what happens, you’re in a game,” guard Chris Snee said.

Even though Umenyiora said: “I never honestly had any doubt we were going to win, I knew we’d come alive at some point,” it sure didn’t feel that way inside MetLife Stadium. The Giants needed an Eli Manning touchdown pass to fan favorite Victor Cruz with 5:58 remaining and then they finally put the clamps down with some fearsome defensive pressure to secure a 20-17 victory over a Dolphins club that is now 0-7.

“When there are opportunities to win games you have to take them,” Manning said. “I think we are doing good jobs of finding ways to win.”

That the Giants (5-2) had to find a way to win against a team that firmly is a top contender for the Andrew Luck sweepstakes is disturbing, especially considering what comes next. The Giants face the Patriots on Sunday, the start of a brutal five-game stretch, and there is no conceivable way the performance they put in to barely subdue the Dolphins is going to cut it with the steep rise in competition.

“We weren’t as sharp as we thought we were going to be,” Tom Coughlin said.

The Giants showed no outward signs of relief and the only reason they won may be that they had Manning and the Dolphins did not. Manning again was brilliant on a day when the Giants had no running game (50 yards from Ahmad Bradshaw, 10 from rusty Brandon Jacobs). Manning was forced into a season-high 45 passes and he completed 31 of them for 349 yards with touchdowns to Mario Manningham and Cruz. Once again, Manning did not throw an interception and at times he was the only reason why the Giants were even in the game.

“He lit it up,” Cruz said.

“It was clearly one of those days running the ball was just not happening for us, so you got to go with what’s working,” added Snee. “Eli was extremely hot and our receivers were getting open.”

Trailing 14-3, Manning directed an 84-yard drive that ended with his 7-yard scoring pass to Manningham just eight seconds before halftime to cut the margin to 14-10, but Dan Carpenter’s 40-yard field goal made it 17-10 early in the third quarter. From there, the Giants finally clamped down on Bush (15-103), stopped getting burned by Moore’s scrambling and made the Dolphins look like the inept offense they have shown themselves to be.

A 29-yard field goal by Lawrence Tynes pulled the Giants within 17-13 early in the fourth quarter and the winning points came when Manning from the Miami 25-yard line found Cruz (7-99) over the middle. Cruz eluded cornerback (and former Giant) Will Allen at the 10-yard line, spun out of an Allen tackle attempt at the 5-yard line and lunged into the end zone.

Sacks by Mathias Kiwanuka, Justin Tuck and Umenyiora in the last two Dolphins possessions led to Corey Webster’s game-clinching interception.

“You have to be able to go out there and play as an underdog, but you also have to be able to go out there and play when you’re favored,” Kiwanuka said. “That’s something we’re still learning. I think we took a big step today, but we’ve got to get to that point where we can go out there and smash everybody in the face no matter what.”

paul.schwartz@nypost.com