NFL

QB call will determine Rex’s future with Jets

CORTLAND — Rex Ryan gets a do-over most NFL coaches don’t get. He gets a second chance to handle a quarterback controversy. Let’s hope he does a better job than he did last year.

You will recall what a mess the Jets’ quarterback situation became. Ryan stuck with a slumping Mark Sanchez far too long then started third-stringer Greg McElroy ahead of second-stringer Tim Tebow while professing the Jets had the three best quarterbacks in the NFL.

By the time the season was done, Sanchez’s confidence was shattered, McElroy was injured and Tebow simply was ignored.

General manager Mike Tannenbaum took the fall for the fiasco, losing his job. Ryan survived, but heads into his fifth season as the coach on shaky ground.

How he handles the current quarterback controversy — err, competition — could go a long way in determining whether he has a chance to keep his job next season. The pressure clearly is on Ryan to get it right this time when he decides between Sanchez and rookie Geno Smith.

“It has to be the right decision,” Ryan said yesterday as the Jets reported for training camp at SUNY Cortland.

The competition begins with the today’s first practice. When he makes his decision, Ryan needs to choose with his head and not his heart. He promised Smith, the second-round pick from West Virginia, would get “a fair shake.” But it feels like this is Sanchez’s job to lose.

It will be difficult for the head coach to forget Sanchez led the Jets to the AFC Championship Game in his each of his first two seasons. They came into the league together and nearly reached the Super Bowl together.

But the Jets have gone 8-8 and 6-10 over the past two seasons with Sanchez throwing almost as many interceptions (36) as touchdowns (39. Still, giving up on a former first-round pick and someone who looked to have so much promise early in his career would be a scar on Ryan’s tenure as the Jets head coach. Sanchise Lost.

Both quarterbacks said the right things yesterday, though each made it clear he was ready to compete for the starting job.

“I have a job to do and which is to come in and compete,” Smith said, “and that’s what I’m going to do.”

Ryan said “several other people” will be involved in the decision on who will be the starter, but only Ryan will receive the backlash or the praise. It’s his job that’s on the line.

Sanchez could make it easy for Ryan by outplaying Smith during the preseason, something that should be expected given one is entering his fifth year in the NFL and the other hasn’t played a down. But Sanchez looked so lost at the end of last year he still must prove he isn’t a shot quarterback. If Smith performs well, there will be pressure for the coach to make a switch. It could be a tough call, a franchise-defining decision.

As Sanchez arrived at camp yesterday, photographers raced from one corner of the building to another, trying to capture photos as he collected his things from a car. But before Sanchez finished unloading his gear, Smith appeared at the opposite end of the building ready to speak to the media. In an instant, the cameras left Sanchez and scurried to position themselves to photograph Smith.

There’s an omen in there somewhere. There figures to be a time when Smith becomes the leader of the Jets and no one will care about Sanchez. Whether that begins sometime during this training camp, this season or next year remains the 800-pound question weighing on Ryan.

Last year, Ryan wanted us to believe Sanchez was a championship-caliber quarterback, and McElroy and Tebow were just as good. We found out the Jets were a team without a single quarterback, a key reason why they finished 6-10.

Now Ryan gets another chance to make the right choice. He won’t get a chance for strike three.

george.willis@nypost.com