Joe Johnson knew it was over from the moment the ball left his hand.

“That’s why I kind of faded back and my trot was kind of swagged out,” Johnson said.

It took 22 games, but the Brooklyn Nets $89.3 million closer finally notched his first save.

Johnson’s 23-foot step-back buzzer-beater from the right wing as time expired enabled the struggling Nets to escape with a 107-105 double-overtime victory over the relentless Detroit Pistons on Friday night at Barclays Center.

“I don’t think anybody wanted to play a third overtime,” Deron Williams said. “I guess he knew we needed to get to Chicago.”

The Nets (13-9) did everything in their power to lose this one -- from blowing a 17-point lead, to trailing 90-84 with 1:32 left in the fourth quarter, to missing their first six shots of the second O.T. -- but Johnson wouldn’t let them.

After Kris Humphries accidentally tipped a game-clinching rebound right to Kyle Singler for the game-tying layup, the Nets called timeout and drew up an isolation play for Iso Joe.

Johnson caught the ball and began to drive to his right while being guarded by the lanky Tayshaun Prince. As soon as Prince began to close off the lane, Johnson dribbled the ball behind his back, gained separation and launched an off-balance pull-up with his feet touching the 3-point stripe.

Swish.

All Pistons coach Lawrence Frank could do was offer a blank stare. All comedian Jerry Seinfeld could do was offer was a look of astonishment.

Just like that, Joe Cool had regained his swagger.

“Joe closed the door for us, and that was really exciting,” Nets coach Avery Johnson said.

Joe Johnson, who came in averaging just 16.3 points on 41.9 percent shooting, ended up with a game-high 28 points -- five of them coming in the second extra session -- on 12-for-22 shooting in 52 minutes. Over his past three games, the 31-year-old veteran is averaging 22.3 points and shooting 52 percent.

“I wish I could’ve been in mid[season] form to start the season,” Joe Johnson said. “But it’ll come. It’ll come.”

Avery Johnson has been saying it would come in mid-December.

“It’s the middle of December,” Avery Johnson said. “It’s time now, Joe. ... It wasn’t a secret that we were going to give him the ball and ride his back. That’s what we’re looking for from Joe.”

On Friday night, Brook Lopez returned from a seven-game absence due to a sprained right foot, and logged 24 encouraging minutes. He might even play on Saturday night against the Bulls.

Gerald Wallace played like his nickname, “crashing” all over the hardwood and finishing with 25 points, 10 rebounds and 2 blocks. Deron Williams added 17 points and 6 assists, while Andray Blatche contributed 16 points in 24 minutes off the bench.

As Avery Johnson pointed out, it was a total-team effort.

“That’s the kind of team I saw in Boston,” the Nets coach said. “The guys were just mentally and physically tough.”

But when it came down to it, the only reason the Nets were able to snap their four-game home losing streak was because they put the ball in Joe Johnson’s hands -- and he delivered with confidence.

It was his first game winner as a Net. About time.

“It was kind of surreal,” Joe Johnson said.