As usual, one or more of the top picks in next week’s NFL draft won’t make it to training camp on time. They’ll come to be known as holdouts and referred to in pejorative terms for what will be perceived as unwarranted selfishness.

They haven’t even completed a pass or made a tackle or scored a touchdown, the rant will go. How dare they demand even more millions than the franchise is offering.

Here’s why: Al Lucas.

A spokesman for the Los Angeles coroner — the real thing, not some morbid team nickname — said Tuesday that an official cause of Lucas’ death could not be issued until test results of Lucas’ brain tissue were returned. But the Arena Football League team for which Lucas played, the Avengers, said it presumed his death was caused by a spinal cord injury.

Lucas was attempting to make a tackle Sunday in the Avengers’ game against the New York Dragons. He bent down. A blocker and the ball carrier tumbled over him. Lucas hit the ground.

It was a scene every football fan has witnessed a thousand times over, the classic three yards and a cloud of dust.

And what followed was a scene every football fan has witnessed dozens of times. The injured player lay motionless. Medical personnel rushed to his aid. A hush fell over the arena. The player was stabilized to a stretcher and wheeled off the field and out of view.

The only thing that was shocking about what happened Sunday on L.A.’s Staples Center football field was, thank everyone’s lucky stars, that it doesn’t happen more often.

Lucas didn’t move again.

As the Avengers continued to go about their business of beating the Dragons, 66-35, Lucas was rushed to California Hospital Medical Center. There, he was pronounced dead. A wife and 1-year-old daughter survive him.

Al Lucas, who died playing football at 26, is why professional football players ought to hold out for every penny they can get, no matter how ridiculous it sounds for a guy to be paid several million dollars to play a kid’s game from the sandlot. We may call pro football a game, but it is a dangerous choice of employment.

It can debilitate in the long run. It can paralyze in short fashion.

It can, as the Lucas tragedy reminded, even kill, maybe even instantly. All it takes is getting hit in the wrong place or in the wrong position.

A replay showed the blocker’s leg striking Lucas’ helmet. That was it. And that happens all the time.

The players are getting bigger and wider and stronger — Lucas was 6-foot-1 and 300 pounds — and their armor is getting more and more absorbent of all the collisions. As a result, the blows being delivered, intentionally and inadvertently, are getting harder and more stunning.

What befell him is why I don’t understand how anyone can begrudge pro football players making gazillions, or demanding gazillions, to entertain us like the modern-day gladiators they’ve become. Any of the dozens of collisions they incur during a game can render them paralyzed or worse.

That isn’t to say that the hazards of one’s employment should determine the remuneration, although it would seem fairer for armed servicemen and women in Iraq to reap more rewards for being there than Halliburton executives who are profiting from the war at their desks. But pro football players are worth whatever they can squeeze from the market.

These guys literally put their necks on the line.

This time, with a tragic result.