SPURS

It was Boston’s most thrilling win of the season. It was the Spurs’ biggest facepalm of a defeat.

The Spurs led by as many as 32 points in the first half and by 31 in the third quarter and couldn’t put the game away.

The loss was particularly devastating for a 31-31 Spurs team clawing to hang on to one the Western Conference play-in slots.

“If you don’t feel disgusted by it, frustrated by it. … We were up 32 points,” DeRozan said. “Give them credit, they played hard, but we can’t let a 32-point game get away from us.”

It did not help the Spurs’ cause Jayson Tatum took the opportunity to channel his inner Larry Bird.

The 23-year-old forward finished with 60 points on 20 of 37 shooting. In doing so, Tatum set a new career best for the second time this month, surpassing the 53 points he registered in an April 9 overtime win over Minnesota.

Of all the luminaries in Celtics history, only one — Bird — had scored 60 points in a game before Tatum did it Friday.

It was also the second-most scored on the Spurs, one fewer than the 61 points Houston’s

James Harden slapped on them in April 2019.

“He did exactly what a great player is supposed to do,” Celtics guard Jaylen Brown said. “He was efficient, led us, hit timely shots. Big-boy basketball.”

For the Spurs, it was a tale of two halves Charles Dickens might find hacky.

They ran circles around the Celtics in the opening two quarters, matching a season-scoring high for the opening two quarters while shooting 71.4 percent.

They made only 38 percent after halftime, and were outscored 95-48 in the second half and OT.

No player signified the Spurs’ brutal regression to the mean more than Dejounte Murray, who was 9 of 9 for 20 points in the first half and 1 of 9 for four points in the second.

Some players said they could feel the game slipping away before it did.

“There was a time when we were up 10 of 15 points, and every time they scored, we were kind of walking around like we were losing,” guard Lonnie Walker said, “rather than knowing we were up and in control of it.”

Spurs coach Gregg Popovich hopes his young team can take the blown lead as a learning experience.

It was as if the Harlem Globetrotters and Washington Generals swapped jerseys at halftime.

“It’s a matter of mental toughness, understanding that there are a lot of plays and that’s what the 48-minute game is all about,” Popovich said.

“People are going to make runs. You can’t let yourself get down, because it you let it affect you, all of sudden transition defense isn’t as good. You are not as physical with the halfcourt defense. You get sloppy and try to do things too quickly on offense, and all of a sudden the ball stops because their defensive pressure is up.”

Even when the Spurs had good fortune in the second half, it found a way to turn bad.

With 31.2 seconds remaining in OT and the Spurs ahead 137136, Jakob Poeltl appeared to pick off a lob intended for Boston’s Robert Williams at the rim.

Officials ruled Poeltl fouled Williams while leaping for the ball, a call overturned by a Popovich challenge.

Had referees not blown the whistle in the first place, the Spurs would have had the ball and a chance at a game-sealing basket.

Instead, Poeltl and Williams were placed in a jump-ball situation, which the Celtics center won. Moments later, Brown swished a corner 3-pointer to put Boston ahead for good.

Afterward, Popovich said he understood why his successful challenge led to a jump ball, but

lamented the outcome.

“It would be great to get the ball, that’s for sure,” Popovich said. “But those are the rules.”

In the end, it was a game neither team could quite believe.

The Celtics won despite leading for only 52 seconds of regulation.

They didn’t take a lead in the second half until Tatum converted a 3-pointer to make it 127-126 with 37.4 seconds remaining in the fourth quarter.

Boston coach Brad Stevens said he left the arena with mixed emotions about his team’s monumental rally.

“I’m happy with the comeback, I’m happy with the effort,” Stevens said. “But that was ridiculous, the way we started the game.”

The Spurs can say the same, except in reverse.

Chances are good they will be feeling their collapse in Boston for a while.

The return home Sunday to face Philadelphia, the Eastern Conference’s No. 2 team, at the AT&T Center. Then they embark on another four-game road swing that begins with a doubledip against NBA-leading Utah on Monday and Wednesday.

Their second-half pratfall in Boston could well lead to a fourgame losing streak, a tough blow for a team in the thick of a playoff race.

“Especially at this time of the season, we have to figure a way to pull these games out,” DeRozan said.

The next time the Spurs are offered a chance to name their score, Popovich hopes they will stick with zero-zero.

“It’s a tough, tough lesson,” Popovich said. “But that’s the way it is.”