OAKLAND – It’s old and cranky and probably bitter about being abandoned.

That would explain why the magic of Oracle Arena, once the most reliable component of recent seasons – the best stretch in franchise history – has turned on the Warriors this season.

The cloak of invincibility they used to wear like a shield has been shot through with holes signifying vulnerability, the latest example coming Saturday in a 126-91 shellacking under a torrent of 3-pointers by the openly transitioning and largely nondescript Dallas Mavericks.

For all the talk about chasing the No. 1 seed in the Western Conference – which still is probable – and having home-court advantage for as much of the postseason as possible, the Warriors in this game were light on both spirit and performance.

The talk might be appropriate for reasons of identifying a goal, but it is profoundly hollow in the face of reality. With a home record (25-11) that is one game better than the road record (24-12), the Warriors no longer have a real home-court advantage. It has been weakening for a couple years, and now it’s as gone as the easily affordable ticket.

“It is weird,” Draymond Green said. “You’re supposed to win at home. And you expect to win at home. We’ve had quite a few letdowns this year.”

This 35-point loss is, however, the worst in 200 games at Oracle under coach Steve Kerr. And it comes 18 days after the previous worst, a 33-point drubbing by the Boston Celtics on March 5.

The Warriors went 39-2 at home in 2014-15. That’s a home-court advantage. They were 39-2 the next season, solidifying their dominance at Oracle. They thought they might be slipping when they were 36-5 at home in 2016-17.

The real slip came last season, when the Warriors were no better at home than on the road, posting 29-12 records in both columns. That, folks, is not a home-court advantage at all.

The Warriors, coaches and players, expressed a strong desire, to make this season, the last in Oakland and at Oracle, special and memorable. Give Oracle a proper farewell. Go out with a splash.

This was the sixth time this season they’ve lost a home game by at least 20 points. The Bucks (134-111 on Nov. 8) were terrific, the Thunder (123-95 on Nov. 21) were rolling, the Raptors (113-93) were out to make a statement, as were the Celtics (128-95).

But the other two blowouts, to the Lakers (127-101 on Christmas Day) and the Mavericks should be unfathomable, no matter how bored the Warriors might be with the regular season.

“You kind of sensed the energy wasn’t there,” Green said. “That’s kind of normal in a game like that. I didn’t really get the sense we would lose by 40.”

It was 35, but it may as well have been 40, as Dallas led by as much as 43.

The Mavericks, who had lost their last 12 games at Oracle, attacked from the start and never backed off. Nor was this 28-44 team put in its place. Dallas drilled 13 3-pointers in the first half and finished with 21 triples (in 49 attempts), one short of their season-high and tying the Rockets’ total (on Jan. 3) for the most against the Warriors this season.

Houston’s 21 triples also came at Oracle.

What magic?

“It was their offense and it was our (defensive) breakdowns,” Klay Thompson said.

The Warriors lacked verve at both ends. They defended as if they had no respect for the Mavericks and compounded that by shooting 40 percent overall and only 13.3 percent (4-of-30) from distance.

The Warriors were down by 12 (14-2) less than four minutes after tipoff, down by 23 (51-28) less than three minutes into the second quarter. Six different Mavericks made at least two triples, with rookie sensation Luka Doncic banging four and Dirk Nowitzki, in what may be his last season, draining a season-high five while totaling a season-high 21 points.

“I think everybody in that locker room has gotten their asses beaten at home before,” Kevin Durant said. “I know this experience is different, with how much winning we’ve done the last few years. But we’re still in the NBA. Guys have been a part of terrible games, along with the great games as well.

“The good thing about it is we play (Sunday) night, too.”

Well, yes. The Detroit Pistons come into Oracle for their annual visit. They won here last season. They’re nearly as beatable as the Mavericks, as if that matters.

Oracle doesn’t mean what it once did for the Warriors, who don’t exploit its advantages as they have in the past. If the Warriors are to win another championship, we’ve seen enough to know home court won’t be the deciding factor.