Head coach Erik Spoelstra

Head coach Erik Spoelstra of the Miami Heat reacts during the third quarter against the Cleveland Cavaliers in Game Four of the Eastern Conference First Round NBA Playoffs at Kaseya Center on April 28, in Miami, Florida. 

MEGAN BRIGGS/GETTY IMAGES/TNS

MIAMI — How much fight did the Miami Heat have left? How much bone- deep belief could they muster? Any at all? The answers came fast Monday night. The game, like this series, fell like an avalanche on the Heat, starting the clock on their offseason after Miami was swept like dirt from the NBA play-offs’ first round by Cleveland.

Bam Adebayo had called the Heat’s 37-point loss in the previous game “embarrassing.”

This one was by 55 — the third-worst playoff defeat by any team in NBA playoff history.

This series has exceeded mere embarrassment for a proud franchise built on “Culture,” a team that dropped four straight games to the No. 1-seed Cavaliers by a combined 131 points. This wasn’t much less than a public humiliation finished by the Cavs’ 138-83 close- out rout, the Heat’s most lopsided post-season defeat ever.

“We are humbled,” coach Erik Spoelstra said. “It’s a shame we’ll be remembered for these last two games and this sweep. I feel for the locker room, to overcome a lot of things and then (win) those two play-in games. I’m gonna spend all summer over-analyzing everything.”

This is the worst, most dispiriting playoff ouster by a major South Florida pro team since the 62-7 Dolphins loss in January 2000 that chased Dan Marino into retirement.

The Heat hole Monday was 43-17 after the first quarter, an insult to the fans who filled the downtown arena for Miami’s eighth consecutive home playoff loss.

“To get down that quick, a little bit of doubt creeps in,” said Tyler Herro, held to four points.

The Butler did it

The series was an abomination of epic scale for Miami, but one that maybe shouldn’t have shocked following a 37-45 regular season and 10th playoff seed that worked up in the play-in to No. 8. The Heat were that mediocre in a season hijacked by the Jimmy Butler drama, suspensions and trade.

And Cleveland is that good — an expertly constructed team that led the league in scoring and and plays great defense as well. Ask Herro, who was 1-for-10 shooting.

Herro admitted during this series he felt lost post-Butler, and seemed to speak for his team.

“Obviously, I know I need Jimmy to win. If we had Jimmy right now, I feel like it’d be a completely different situation,” he told The Athletic. “We probably wouldn’t even be the eighth seed. So finding that middle balance of, like, damn, we need him, but also understanding, [bleep], that’s his career and what he wants is ultimately his right to want what he wants. It was just tough to be in the middle of both sides.”

Miami certainly was better with Butler but to say the series would have been a “completely different situation” with him is a bit absurd (not to mention sort of a veiled insult to Adebayo.) Heat were never going to win a fourth NBA crown as long as Butler was their best player. They won’t win now with Herro and Bam Adebayo as their two best guys.

This might be the worst game I’ve ever watched,” Ernie Johnson said.

“This is quitting at its finest,” added Charles Barkley.

Shaquille O’Neal: “Miami has no fight.”

The offseason can’t get here soon enough, and Pat Riley and company need to attack it — and win it.

Two things looking ahead:

Nobody on the Heat roster should be considered untouchable or above trading. I’d try to hang onto Herro or Adebayo but be willing to trade either, and anybody, else for a prize big enough.The prizes I have in mind are Giannis Antetokounmpo of Milwaukee or Kevin Durant of Phoenix. Durant, still great at 36, has been sought three previous times by Miami. Fourth time’s a charm? He may be available. So might Antetokounmpo. The cost would be steep, but it’s time for Miami to swing big.

Does Riley, at 80, have one last whale in him? We hope so.