LAS VEGAS — Ding, dong. The Avs are dead.

Don’t tell me about a championship window for a hockey team that keeps beating its head against the same wall and somehow expects a different result.

This is insanity. And it’s got to stop.

A disgusting 5-3 loss to Vegas screamed the problem with the Avalanche isn’t talent, but a complete and utter failure of leadership.

Why is coach Jared Bednar still here?

He never kicks butt and takes names. He will tell you it’s not his job to stoke the fires of competitiveness in his players. He fails to take responsibility for the Avalanche’s long, annoying habit of folding in the face of adversity.

So what does Bedsy do for this team? Hand out orange slices in the locker room?

On a Sunday so sad it will live in infamy in Colorado sports history, the Avs blew the entirety of an early three-goal lead in a wretched 13-minute stretch of the second period.

After the emotional bump of getting back star defenseman Cale Makar from injury, they watched star center Nathan MacKinnon limp off the ice after taking a puck to the knee.

Horrible luck? Yes. But the Avs wear adversity like an excuse. In defeat, the vibe in the Colorado locker room was heavy as a gravedigger’s shovel.

One loss from being swept out of the Western Conference finals, instead of expressing outrage or defiance after Vegas pushed his team to the brink of playoff elimination, Bednar evaluated the Avalanche’s collective spirit with a what-can-you-do shrug.  

“It’s low,” Bednar said Sunday, in a monotone as flat and lifeless as his team’s heartbeat. “As low as it gets.”

In MacKinnon, Colorado is blessed with the league MVP.

In Makar, this team has a generational defenseman that comes along as often as Bobby Orr.

In Gabe Landeskog, the Avalanche has a captain for the ages.

And what do the Avs have in Bednar?

A coach who can consistently find a way to mess it all up.

A hockey team that looked nearly unbeatable through 82 regular-season games and two rounds of the playoffs is now one defeat from being the biggest waste of talent in recent league history.

Facing a must-win situation, the Avalanche showed the heart of a choker. This team had won 49 times in a row with a three-goal lead.

OK, so that streak was due to end sooner or later.

“It’s gonna happen,” Makar said, “but it can’t happen at this time of year.”

With Makar playing for the first time in this series after suffering a shoulder injury earlier in the playoffs, Colorado dominated the first period with not one, not two, but three scores.

“It just felt like we ran out of gas,” Makar said.

In the second period, Colorado took its foot off the accelerator pedal and tossed its hammer in the trunk. The burgundy-and-blue bandwagon didn’t merely stall. It careened straight into the ditch.

I’ve only borne eyewitness to 95% of the Avalanche’s 275 playoff games since 1996. And these 20 minutes, when Colorado turned a three-goal lead into something that smelled like burnt toast, were as revolting as anything in the franchise’s postseason history since the Red Wings chased goalie Patrick Roy and humiliated the defending champs 7-0 in Game 7 of the Western Conference finals way back in 2002.

You can look up the grim details of this epic collapse. Rewatch the video, if you have the stomach for it. But I can tell you how it felt.

It felt like a house fell on the Avs.

Let’s give props to MacKinnon. He tried to play through his pain. “You might have to kill him to get him off the ice,” Colorado goalie Scott Wedgewood said.

But instead of fighting back, Colorado surrendered.

When Tomas Hertl gave Vegas its first lead 8 minutes, 21 seconds deep into the third period, it was all over but the crying for the Avalanche. An empty-net goal by the Knights in the final minute was nothing more than the final nail in the coffin.

The silence in the losing dressing room was deafening. And incriminating. In a violent sport where grit and intensity often make the difference between winning and losing, these Avs take on the detached, passionless nature of their coach.  

“Everyone,” Bednar said, “is down in the dumps.”

Well, boo hoo.

A little over a mile north of where the Avs beat themselves stands Sphere, which shines brighter than anything on the Las Vegas Strip.

When No Doubt or the Eagles aren’t rocking the joint, the venue shows the “The Wizard of Oz” in an experience so immersive you feel as if you might get swept up in a tornado.

And when Dorothy’s house falls on the Wicked Witch of the East, your seat shakes.

During the second period, when Colorado’s championship dreams got blown away, it was so loud in this Vegas hockey barn that my seat shook.

Ding, dong.

These Avs are dead.