Column: Justin Herbert, four-down attack make Chargers legitimate Super Bowl threat

If you are a San Diego sports fan who roots against the NFL team owned by Dean Spanos, you’ll never get a lecture from me.

However, while you’re sticking pins into a blue-and-gold voodoo doll, consider yourself warned:

Justin Herbert is capable of breaking your heart. He might do it this winter. Many NFL norms don’t apply to him.

Just 20 starts after the dopey Lions and other chronic klutzes chose not to draft him, Herbert has become an NFL star. If he weren’t such a nice dude, he’d be accused of cruelty to his fellow man. He puts defensive opponents under extreme duress, when most quarterbacks can’t.

Stopping Herbert and Co. on three downs is very hard, but get this: It’s also not good enough.

You have to stop them on fourth down, too.

A good Cleveland Browns team couldn’t do it Sunday in the Kroenke Dome, and Herbert led the Chargers to a 47-42 victory in a back-and-forth contest between AFC teams that each brought in a 3-1 record.

The Chargers have themselves a sophomore quarterback whose rare traits — smart passing that threatens the whole field; 4.71 sprint speed that Sunday produced a scoring run — encourage the team’s rookie head coach, Brandon Staley, to flash a green light almost always.

Opponents are cracking under the superhuman task.

Already challenged by injuries that diluted them before and during the game, the Browns saw Staley ask Herbert and Co. to convert on fourth down with two, four and seven yards needed.

He went 3-for-3, reviving two drives that would each lead to a touchdown.

On fourth down this year, young Herbert is Steph Curry shooting free throws. The Chargers (4-1) are converting at 90.9 percent (10 for 11) for the season.

Yes, the Chargers received a huge gift in that area Sunday.

An official wrongly flagged a Browns cornerback for pass interference instead of flagging Chargers receiver Mike Williams for the same or just allowing the incompletion.

Browns corner A.J. Green had established superior position. He was between Williams and the ball and guilty of less influential hand fighting than Williams.

Instead of the Browns getting the ball at L.A.’s 41 on a fourth-and-4 incompletion — the best call — the Chargers got a reprieve plus 33 yards. They cashed that gift card for a TD that tied the score at 35-all. “Point expectancy models” understate such flags. A defense that’s already gasping can’t overcome them.

So the Chargers now have won two games against AFC playoff contenders in which they benefited hugely from a pass-defense penalty on fourth down in the fourth quarter.

To some extent, they earned that good luck.

Herbert is able to throw from sideline to sideline and deep downfield, with rare power and accuracy. His passes can astound even NFL veterans. “The ball speeds up the faster it gets down the field,” said Drew Brees, now with NBC. Giving the passing game an explosive dimension underneath, Austin Ekeler is lethal on screens and went 29 yards Sunday for the TD that pulled L.A. to 42-41.

Most passing offenses earn less trust from their play caller.

In contrast to Staley giving Herbert extra slack — extraordinary slack for a second-year player — Browns coach Kevin Stefanski showed less faith in his passing offense when crunch time arrived.

From his 15 with 2:55 left in the fourth quarter, Stefanski had quarterback Baker Mayfield hand off on third-and-9.

The Browns led, 42-41.

Mayfield was having a fine game, with much help from an explosive ground attack. Impressively, Bill Callahan’s offensive line, hit hard by injuries before and during the game, kept the Browns’ O on schedule most of the contest.

Mayfield is no worse than a mid-tier NFL quarterback, but Stefanski’s decision acknowledged that the first player chosen in the 2018 draft is not in Herbert’s class in this crucial aspect: Moving the chains on third-and-long (even harder on a long field).

The handoff led to a punt, which led to the Chargers getting the ball near midfield and driving for what stood as the winning points.

Herbert accounted for five TDs, four on passes. He finished 26 for 43 for 398 yards without an interception.

Improving on his rookie season, he has outplayed Patrick Mahomes, Derek Carr (who was on a roll) and Mayfield in the past three games.

A few years ago when Dean Spanos told an NFL owner, “Now I know how Art Modell feels,” as reported by author Mark Leibovich, it wasn’t a happy parallel the Chargers owner was raising. Modell was vilified by Ohioans for moving the Browns out of Cleveland, and some San Diegans vilified Spanos in similar fashion.

Now a potential second Spanos channeling of Modell is in play, only it’s one Spanos would welcome. Remember, Modell raised the Lombardi Trophy five years into his Baltimore venture. The Chargers, five years into their L.A. venture, are alone atop the AFC West and have a quarterback with a Roman numeral look to him.