NFL

Giants took roller-coaster ride to unlikely title

INDIANAPOLIS — The Giants were living proof this season that it isn’t how you start, but how you finish.

And boy, what a finish it was.

If anyone had suggested as late as halftime of their Christmas Eve game against the Jets that Tom Coughlin’s team would go on to beat the Patriots in Super Bowl XLVI just six weeks later, you would have demanded they get drug-tested.

Standing at 7-7 after an ugly home loss against the Redskins and owners of a four-game losing streak that dropped them from 6-2 to 6-6, the Giants seemed much more liable to get Coughlin fired in January than make hotel reservations for Indianapolis in February.

But something lit a spark in the Giants that day at MetLife Stadium, because once they rallied for a 29-14 win over Rex Ryan’s Jets, Big Blue became a Big Blue Freight Train.

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COMPLETE GIANTS SUPER BOWL COVERAGE

Five more victories later, Eli Manning was a Super Bowl MVP again and the Giants, almost unbelievably, were world champions again — the first nine-win finisher to pull off that feat since the NFL went to a 16-game schedule in 1978. It was as much of a roller-coaster ride as that statistic would suggest, so come along for the highlights (and a few lowlights, too):

GREEN BAY, REDUX

It was only four years ago the Giants went into Lambeau Field as underdogs in the NFC Championship and eliminated the Packers in an overtime thriller. The setting was different (Divisional round), and the Green Bay quarterback was different (Aaron Rodgers), but the result was the same — a 37-20 Giants win that rendered the Packers’ 15-1 regular season meaningless.

CAPTAIN COMEBACK

After producing just 14 fourth-quarter comebacks in his first seven NFL seasons combined, Manning suddenly morphed into Houdini this year by leading an incredible seven rallies in the final period — the capper, of course, being the final, frantic seconds of the Super Bowl.

THE MISS

How narrow of a tight rope did the Giants walk? If Tony Romo completes one pass to a wide-open Miles Austin in their first meeting with the Cowboys, the entire Super Bowl run never happens. Leading 34-29 with three minutes left and facing third down, Romo saw a streaking Austin behind the Giants’ secondary for what would have been the clinching touchdown but overthrew him, paving the way for another Manning comeback.

THE INEXPLICABLE

The Giants swept Tom Brady and beat Rodgers in the playoffs, but they were no match for Rex Grossman. Not only did the Sexy Rexy-led Redskins beat them twice, they did so handily while Grossman threw for a combined 490 yards and three touchdowns (with two interceptions) in the process. The Giants also ended up providing nearly half of the 5-11 Redskins’ victory total. That made about as much sense as Coughlin’s team losing at home to the Seahawks by double digits, which also happened.

THE GRIND

A midseason six-game stretch that included the Packers, 49ers, Saints, Eagles and Cowboys looked like a death march when the schedule came out, and that’s almost what it became as the Giants went 1-5 in that span and nearly blew up their season. The low point was a 49-24 nationally televised blowout in New Orleans in which Drew Brees dismantled the Giants’ defense. But Coughlin & Co. had the last laugh, avenging two of those losses (Green Bay and San Francisco) in the playoffs.

THE INJURY

Who knew that a knee injury to famous draft bust Ted Ginn Jr. in the NFC title game would prove so crucial? Ginn was the 49ers’ punt returner, but was hurt in the Divisional round against the Saints, forcing San Francisco to go with Kyle Williams — son of White Sox GM Kenny Williams — in that role. It ended up torpedoing the Niners’ season when Williams fumbled twice after halftime, including a critical turnover in overtime that set up the Giants’ thrilling win.

THE UNDRAFTED

FREE AGENT

Not even the Giants themselves knew what they had in Victor Cruz as recently as Week 2 of this season. The second-year pro from Paterson, N.J., was so shaky that GM Jerry Reese brought in 35-year-old Brandon Stokley to play slot receiver after Cruz dropped a pass in the season-opening loss to Washington. But 82 catches, nine TDs and a franchise-best 1,536 yards later (including a 99-yard score against the Jets), Cruz was dancing the salsa into the Giants’ record books and asserting himself as one of the most dangerous pass-catchers in the entire league.

THE CATCH

Move over, David Tyree, because you now have company in Giants Super Bowl lore thanks to Mario Manningham’s 38-yard sideline grab in the final seconds of the Super Bowl that set up the game-winning touchdown. Manningham’s catch didn’t have quite the degree of difficulty as Tyree’s famed helmet reception, but it was no less impressive or important.

bhubbuch@nypost.com

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