SAN FRANCISCO — Steph Curry and Draymond Green each hugged Klay Thompson after a heartfelt pregame tribute to their former teammate.

It was all love. Then the ball was tipped. It didn’t take long for Curry and Green to treat Thompson like they would any other opponent: with ferocious competitiveness.

Curry defended Thompson, and both he and Green hit early 3-pointers over the four-time champion. Their lifelong brother had his moment with a sold-out Chase Center crowd, but it was all business after that.

Teammates for over a decade suddenly on opposite sides, Thompson and Curry delivered moment after moment. Thompson stole Curry’s shoulder shimmy celebration. Curry forced a Thompson airball in a one-on-one situation. Curry pointed at Thompson after canning a 3 over him.

Back and forth they went. A charged-up Chase Center crowd couldn’t take their eyes off them, and why would they?

In Thompson’s first game against the franchise he spent his first 13 years with, he matched his Mavericks scoring high, including eight points in the fourth quarter. But Curry got the last laugh with spectacular shot-making down the stretch, lifting the Warriors to a victory. It was emotional, intense, euphoric, and ended with a 120-117 score.

Thompson finished with 22 points, including six 3-pointers. His splash brother Curry stole the4 show with 37 points and nine assists, outdueling both Thompson and Luka Doncic (31 points), The Warriors (9-2) won their first Emirates NBA Cup group stage game.

In the front of the Chase Center, the massive screen displayed rotating pieces of artwork from local artists of Thompson. One showed him driving his boat accompanied by his dog, Rocco. Another showed 12 different characters of Thompson — “The Multiverse of Klays” — including him wearing a Jackie Moon jersey and another of him holding a water gun.

The Bay Area rallied around Thompson as much as any athlete in the modern era. Oakland and San Francisco wrapped their arms around his charismatic, eccentric personality. They fell in love with his competitiveness and toughness. They tried to lift him up when consecutive leg injuries sidelined him for 941 days in what should have been the prime of his career.

At his homecoming, over 18,000 of them saluted Thompson and gave him a standing ovation for over a minute during pregame celebrations. They showered the franchise icon with appreciation.

Everyone, from Curry, Green and Steve Kerr to Thompson’s new backcourt mate Kyrie Irving, had hoped Thompson would feel the love.

“I want him to be present as much as possible, to really receive the love, receive the flowers that he deserves,” Irving said at morning shootaround.

Love he did receive. Then it was game on.

Thompson opened the game by going at Curry in the post, drawing two free throws. Curry returned the favor by hitting a 3 over Thompson’s late contest — pointing at Thompson when the ball sank through nylon — and Green did the same shortly after. Curry stripped Thompson in the post, and the charged-up Chase Center crowd went wild.

Dallas called a timeout four minutes into the game after Green blocked a Naji Marshall 3-pointer and saved it from going out of bounds, leading to a De’Anthony Melton layup. Golden State only led by five, but the Chase Center was rocking like it was a playoff game, so the Mavericks wanted to quell the momentum.

Curry upstaged his splash brother early, dropping 12 points in the opening quarter. Thompson got on the board with a patented transition 3 on the right wing from Luka Doncic, but the Warriors targeted him defensively. Buddy Hield, Thompson’s replacement, stared at Golden State’s after draining a 3 over Thompson.

Early in the second quarter, Moses Moody blocked a Thompson 3-point attempt, then nearly stuffed a dunk over him on the other end. The crowd — the most animated of the year in this building — was a few inches away from detonating.

A Thompson corner 3 capped a 21-8 Dallas run to start the second quarter, though. He also followed it up with a third triple. After the first, he did a shoulder shimmy — borrowing from Curry — and after the second he pounded his chest. At that point, Dallas led 48-41.

Behind Doncic, Dallas pushed its lead to 11. But the Warriors didn’t let themselves fall out of it. Curry forced a Thompson airball in isolation, then Jonathan Kuminga sparked a fast break with a long rebound and quick outlet pass, resulting in an Andrew Wiggins dunk. Then Curry finished a cinematic and-1 through Thompson, with Thompson shaking his head after the play.

Thompson, who scored 11 first-half points, added a fourth triple after making Wiggins fly by him with a pump fake. But he shot another airball as Golden State ripped off a 13-3 run. Curry threw a right-handed fist pump after Dallas called timeout because of his third 3.

The Warriors held the Mavericks to three points in six minutes, turning a four-point halftime deficit into an 11-point lead. It was the kind of third-quarter Warriors run Thompson had been on the right side of for a decade.

Golden State dominated with curry on the court, but bled points whenever he sat. The bench that has been fantastic for the Warriors in their strong start had an uncharacteristic off game. By the time Curry checked back in with 8:33 left, the Warriors’ lead had turned into a 100-100 score.

Thompson sank a corner 3 to give Dallas a lead and then blew by Wiggins for a finger roll, giving him 19 points. Two minutes later, he gave Dallas a 110-105 lead with a sixth 3, making goggle eyes in front of Curry afterward.

Thompson helped put Dallas ahead by seven, but the Warriors had another run in them. Curry hit a pull-up shot from the elbow extended, then canned a 3 off a screen.

Then with two minutes left, Curry drove past Doncic and bounced in a finger roll, reclaiming a one-point lead. Thompson borrowed his shimmy earlier, and he stole Thompson’s patented snarl.

The Chase Center crowd cheered after Thompson misfired on a 3, and then Curry delivered the dagger. Over Dereck Lively in a switch, Curry rainbowed in the game-sealing 3. He didn’t need to steal any more of Thompson’s celebrations, instead opting for his own night-night.

Curry and Green gave each other a bear hug by midcourt. If it wasn’t already clear, this one meant more.