Boston Celtics’ Kyrie Irving, left, and Gordon Hayward, right, defend against Golden State Warriors’ Kevin Durant (35) during the first half of an NBA basketball game Tuesday, March 5, 2019, in Oakland, Calif. AP Photo/Ben Margot

OAKLAND, Calif.  — DeMarcus Cousins lost his cool and the Golden State Warriors lost at home in embarrassing fashion once again.

Gordon Hayward scored 30 points off the bench, Kyrie Irving had 19 points and 11 assists, and the Boston Celtics ran away from the Warriors early on the way to a 128-95 win Tuesday night in a game that turned testy with the two-time defending champions down big.

Cousins and Terry Rozier received double technicals with 8:44 to play. Cousins was called for his fifth foul on a charge drawn by Aron Baynes, then the fiery Warriors center stood over Baynes in clear frustration. Jayson Tatum bumped Cousins with his right arm and Cousins pushed back with some force, then Rozier entered the fray and he and Cousins traded shoves.

“It was silly. It was nothing, absolutely nothing,” Cousins said without elaborating.

Boogie’s moment summed up an ugly evening of basketball by his team — and fans seeing their final season in the East Bay made a mad dash for the Oracle Arena exits in the closing minutes. It was the Warriors’ fifth home defeat by 20 or more points.

“I’d love to have some magic potion and say we can come out and play with better energy and better discipline and kind of rectify it, but we’ve got to, at some point, stop talking about it and figure it out,” Stephen Curry said.

Curry provided a bright spot with 23 points and four 3-pointers on a night Splash Brother Klay Thompson sat out with soreness in his right knee.

“Klay would have had to play a hell of a game to overcome all that,” coach Steve Kerr said.

Kevin Durant scored 18 points but committed five turnovers, while Cousins wound up with 10 points on 4-for-12 shooting — missing all five of his 3-point tries — and nine rebounds to go with four turnovers.

The Warriors, who had won the last two meetings with Boston, couldn’t overcome a lackluster first half in which they were outhustled on both ends and faced a daunting 73-48 halftime deficit.

“It looked to me like we were jogging up the floor. You can’t play basketball jogging. You’ve got to sprint,” Kerr said. “Your cuts have to be hard. You have to be going all out. We did not go all out and it was embarrassing.”

Tatum scored 17 points for the Celtics, who came in having lost five of six since the All-Star break.

“I think we played with purpose all the way through. We were very businesslike the whole night, even at halftime and just now after the game,” Celtics coach Brad Stevens said. “We know we haven’t played like that enough but It’s encouraging as a reminder that we can.”

Golden State missed its initial four shots and fell behind 11-0 as Boston started 5 of 7 before Curry’s jumper at 8:26. The Warriors made five straight shots and used a 12-2 burst to get right back in it.

Alfonzo McKinnie started in place of Thompson and contributed seven points in 17 minutes.

“It starts with a passion and an anger and an intensity, and it wasn’t there tonight,” Kerr said.

Durant responded to that by asking, “I thought we moved off of joy, now anger?” in response to Kerr’s usual message of playing with joy.

Then, the two-time reigning Finals MVP challenged everyone.

“All around top to bottom, coaches, players, we’ve just got to be better,” he said.

TIP-INS

Celtics: Boston improved to 6-6 on the road against the Western Conference. … Golden State had snapped the Celtics’ 10-game home winning streak with a 115-111 win on Jan. 26. … The Celtics — who shot 8 for 28 from 3-point range in Sunday’s 115-104 home loss to Houston, including 1 of 13 in the first half — were 14 of 34 from deep and got four 3s from Hayward.

Warriors: G Shaun Livingston missed the game with neck spasms. … Andre Iguodala, sporting a new look with his head completely shaved, played after dealing with lower back tightness. … C Kevon Looney missed a second straight game with right pelvic soreness. … McKinnie went through an extensive pregame warmup routine behind the scenes after he left against the 76ers with a bruised left hip. … Golden State earned a winning road record for a sixth straight season. … The Warriors added depth by recalling G Jacob Evans III from the G League Santa Cruz Warriors.

BAYNES’ MINUTES

Reserve Boston big man Baynes will remain on a minutes restriction with Boston playing consecutive nights. He returned Sunday against Houston from an 11-game absence because of a bone bruise in his left foot.

“He’s on a minutes restriction for the foreseeable future, so 15 max, especially with a back-to-back,” Stevens said. “Right now, our thought is that he would be able to play in both games in the next two nights. We will see how he comes out of tonight.”

UP NEXT

Celtics: At Kings on Wednesday.

Warriors: Host Nuggets on Friday.