NFL

Champs must avoid a misstep

It never is a good time to invite Big Ben Roethlisberger and the big, bad Steelers to your house, and it is an especially bad time for the Giants to let them into MetLife Stadium today.

Forget for a moment that Big Ben can have Jason Pierre-Paul, Justin Tuck and Osi Umenyiora hanging onto his tree trunk legs and still find a way somehow to get the ball out to dangerous blurs like Mike Wallace and Antonio Brown, or to dependable tight end Heath Miller, and remember this:

The Giants are coming off back-to-back division victories over the Redskins and Cowboys, and everyone knows how lucky they were in Dallas at the end. Division games carry more weight psychologically than games outside the conference.

Steelers coach Mike Tomlin, a master motivator, has challenged his team to measure itself against the defending Super Bowl champs. Uh-oh. The 4-3 Steelers are the more desperate team because they are a game behind the Ravens in the AFC North. The 6-2 Giants have a commanding lead over the reeling 3-4 Eagles and Cowboys. As we learned this week, you can’t fight Mother Nature … much less human nature.

This marks the start of the second half of the season, a time that has not given Giants fans a great deal of comfort in the Tom Coughlin Era.

The Steelers are an uncharacteristic 1-3 on the road. Tomlin’s 2010 and 2011 teams were 12-4 away from Heinz Field.

No one can safely say how much of a distraction the post-Sandy upheaval will be for the Giants. Of course, if you want one head coach to weather any superstorm, it is Coughlin. And if you want any quarterback, it is Eli Manning.

And yet, as unflappable as he is, Manning was forced to leave Hoboken with his wife and 18-month-old daughter, Ava, for a Manhattan hotel. Not the way you want to prepare for a Hall of Fame defensive coordinator like Dick LeBeau and his

vaunted zone blitz.

“Everybody has to have their antennae up,” Victor Cruz said.

The good news is that Manning won’t have to worry about Troy Polamalu (calf), and outside linebacker James Harrison isn’t the feared headhunter anymore. With the running attacks on both sides not likely to impose their will on the opposing defenses, Manning may have awaken from a sudden malaise and fight fire with fire against Big Ben — with a healthier Hakeem Nicks and Cruz, who can’t wait to sign a new contract that he hopes will make him a Giant for life.

“I’ve just grown to love this organization,” Cruz said. “I feel like they do right by their players. It’s just a positive organization from the bosses all the way on down to the staff. I could just be myself and be open here and ask questions and not feel afraid or ashamed. They were the first team that gave me a chance. That’s the main reason I would like to be a Giant for hopefully the rest of my career.”

Where does playing with Eli rank on his list?

“Oh, it’s No. 1,” Cruz said. “It’s not every day you get to play with a two-time Super Bowl MVP, and be able to pick his brain, and just know his thought processes, his ins and outs, what he likes, what he doesn’t like. I feel like this is history in the making a little bit, and I’m just happy to be a part of it.”

History in the making, how so?

“Just as far as the thing that he started here with the first Super Bowl, and with the last one last year,” Cruz said. “I feel like there’s some history that’s going to be forming here.”

The Steelers, of course, are rich in history. This hardly is a Steel Curtain, but there hasn’t been much talk of any Over The Hill Gang lately either. It helps them that Big Ben and the Steelers are second in time of possession.

“You have to hit him full-on, you have to hit him flush,” said Antrel Rolle, who won’t soon forget Big Ben breaking his Arizona heart at the end of Super Bowl XLIII. “Once he plants those feet, the ball comes out extremely fast, with a lot of force. … And he can make every throw.”

Beware the Steelers. Beware a Giant pitfall.

steve.serby@nypost.com