PHOTO COURTESY PITTSBURGH PENGUINS

As the NHL playoffs lurch toward the upcoming Stanley Cup Final, the almost-completed-three-round precursor has confirmed what Penguins fans had probably feared initially, at least the ones who were still paying attention:

The gap between the Penguins and a legitimate Stanley Cup contender is massive.

The teams that reached the Final Four did so because they’re well equipped in the individual and collective characteristics that are essential to winning a Cup.

Not enough of those clubs are in the Penguins’ bag at present, not by a long shot.

That’s why they’re golfing.

The Rangers, conversely, have an elite goaltender in Igor Shesterkin.

So do the Stars in Jake Oettinger and the Panthers in Sergei Bobrovsky.

New York also has an elite goon in defenseman Jacob Trouba.

The Oilers have a power play that instills fear and oozes game-changing potential even when slumping. They’re also elite at killing penalties, as are the Panthers and the Rangers.

Florida knows how to finish, as the Panthers’ 40-0-3 record in the regular season and 6-0 mark in the postseason when leading after two periods heading into Game 5 against the Rangers confirmed.

The Panthers are also manically committed to playing a grinding, physical, bullying style that eventually imposes Florida’s will.

And nobody, it appears, combines heart and smarts, instinct and hockey IQ, goaltending and star power, and structure and discipline as well as Dallas does.

Imagine the Penguins trying to confront one of these teams with everything at stake when the NHL’s postseason “jungle rules” are in place, when anything goes at the net front, in the corners and beyond.

It’s not a pretty picture, is it?

And the longer this postseason goes, the worse it gets.

Game by game, week by week and round by round.

It was ominous enough in Round One, when eight of the top nine teams in the NHL’s overall regular-season standings moved on to the second round. The exception was No. 4 Winnipeg, which lost to No. 8 Colorado. But was anyone really surprised when the high-octane Avalanche advanced?

Edmonton, ninth overall in the regular season, has reached the Final Four, thanks first and foremost to an elite skill level that perhaps only Colorado can match. The Oilers’ combustibility was on full display in Game 4 against the Stars on Wednesday night. You can wipe out an early 2-0 deficit while facing a potential three-games-to-one hole in the Western Conference Final if you have Connor McDavid, Zach Hyman and Leon Draisaitl.

And you can get to within six games of winning a Cup if you don’t allow any short-handed goals, something the Oilers didn’t do through their first 16 playoff games and the Rangers managed to avoid through their first 14.

The other two semifinalists, Dallas and Florida, allowed a combined four shorties in 32 playoff encounters.

Hopefully the Penguins, who allowed an NHL-worst 12 short-handed goals in the regular season (tied with Montreal, another team that not-so-coincidentally missed the postseason entirely) were paying attention, Mike Sullivan and Kyle Dubas in particular.

It was bad enough, from the Pens’ perspective, when the teams that edged them out in the race for the playoffs all got smoked for openers. The Capitals were swept by the Rangers. The Islanders and Lightning were both eliminated in five games (New York by Carolina and Tampa Bay by Florida).

But since the pretenders have been removed from the equation, it’s become even more apparent the teams that are still playing are playing a different game.