Peyton Manning can’t afford to wilt now

Peyton Manning is set to face off with Tom Brady for the AFC championship. Ed Andrieski/AP

Patriots fans think the Patriots are going to win Sunday because they are confident Tom Brady will play better than Peyton Manning in any big game.

Manning will choke.

That’s the book.

A case can be made that, excluding Super Bowls, this AFC Championship is the biggest, grandest, most-hyped NFL contest of the last 50 years. It’s the 15th playing of the NFL’s 1812 Overture. Bill Belichick has a chance to tie Tom Landry as the winningest playoff coach in NFL history. Brady is already the winningest quarterback in postseason history (18 victories as a starter), and with one more championship, he can join Joe Montana and Terry Bradshaw in the exclusive four-ring club.

The game will be played two days before the 20th anniversary of Bob Kraft’s purchase of the Patriots, and a victory by New England would give the Patriots six Super Bowl appearances in the Belichick-Brady era.

But the single reason this game is the (non-Super Bowl) Game of the Century is the presence of Manning and all the pressure he takes into Sports Authority Field Sunday afternoon.

Manning is the man America wants to see. He is Mr. “Omaha,” Mr. “Cut That Meat!” He is the man with the bull’s-eye on the back of his helmet.

All the pressure in this game is on Manning.

The dirty little secret of this duel is the widespread notion that Manning will somehow choke it all away and hand the game to the Patriots. A good portion of Patriot Nation thinks the Patriots will win because Manning can’t win the big one — especially against Belichick and Brady.

It’s amazing. Manning has morphed into Wilt Chamberlain. Despite all the awards (Sports Illustrated’s Sportsman of the Year in 2013) and commercials, he is disrespected on a par with no athlete this side of Alex Rodriguez. He has amassed passing statistics that may never be broken, but he can’t seem to push past the idea that he’ll fail in the big moment. He cares too much. He’s too nice. And you know where nice guys finish . . .

Much of this is rooted in fact. Some of it is myth.

We know the Patriots have beaten Manning’s teams in 10 of 14 meetings when Brady and Manning were the starting quarterbacks. This includes the 2003 AFC Championship game, when Manning was intercepted four times, thrice by Ty Law. Brady and the Patriots won, 24-14. One year later, in the divisional round, Brady’s Patriots beat Manning’s Colts, 20-3.

We know Manning is a sub-.500 quarterback in the postseason (10-11). Eight times his team was one and out in the playoffs. Manning threw the horrible, across-the-body interception to Corey Graham that closed the book on Denver’s shocking double-overtime loss to the Ravens last January. In Super Bowl XLIV in Miami, Manning threw the pick-6 to the Saints’ Tracy Porter that crushed Indianapolis’s quest for a second Super Bowl championship.

The book is that Manning can’t win in cold weather. He didn’t win on that bitter night in Foxborough two months ago — a night when he was handed a 24-0 lead at halftime.

Oh, and you know the rest of it. Imagine how great Tom Brady would be if he’d had Manning’s receivers through the years. Tom never had Reggie Wayne or Marvin Harrison. He never had the arsenal Manning has now.

Swell. But here’s the counter to all that. Here’s the myth under the avalanche of anti-Peyton propaganda:

Manning never had the defenses that Brady had in New England. Manning never had Belichick as a head coach. Manning is the guy who brought the Colts back from a 15-point first-half deficit in the 2006 AFC Championship game at Indy. That’s when the Colts beat the Patriots, 38-34. A few years later, Manning is the guy who forced Belichick to go for it on a fourth-and-2. Belichick was afraid to punt the ball to Manning.

And why does Brady get credit (and Manning blame) for New England’s “game-winning” drive in the freezing overtime Sunday night game at Gillette? Fact is, neither quarterback put any points on the board in OT. The Patriots scored only because one of the Broncos ran into a punt, giving Brady a first-and-10 from the Broncos’ 13-yard line.

That’s Brady being good and Manning choking? Tom good in cold weather, but Peyton unable to deal with a frosty night?

Manning carries extra weight, even in his new hometown. Last Sunday’s Denver Post kicked off playoff coverage of its top-seeded team with a photo of Manning under the headline, “A Legacy Under a Cloud.’’ After the Broncos hung on and defeated the Chargers, the next day’s Post led with “Whew!”

Something tells me there’s a crisis of confidence in Manning’s own house. And no one exploits this stuff better than the Patriots. Their mere presence in this game is proof of their mental edge. It’s certainly not the depth and talent of the New England roster.

Manning will turn 38 in March. He threw 55 touchdown passes this season. He threw for 5,477 yards. The Broncos scored an NFL-record 606 points in the regular season. Manning is going to be named league MVP for a record fifth time.

But none of it means anything if he loses this game. He will go down in history as football’s Wilt Chamberlain — a guy with all-world numbers who was ultimately owned and dominated by the coach and MVP of the team from New England.