Kenny Atkinson endured a painful — and successful — rebuild in Brooklyn, so he knows exactly what Jordi Fernández is going through.

And the Cavaliers coach said the suffering is going to pay off — even if it feels like the losses will never end.

And the Nets took another Sunday, beaten 106-102 by the Cavaliers before a sellout crowd of 17,804 at Barclays Center, the team’s eighth straight loss.

“No doubt, you definitely go through those moments. You’re going home and you’re taking that L after the game. It’s hard, especially when they start stacking up,” said Atkinson. “Of course you worry if you’re a competitor. But that’s part of it, part of going through a rebuild and part of being a young coach.

“And you see the development … It’ll happen here, because they drafted really good talent. They got really good coaching, good coaching staff, good front office. It’ll break through. You’re just waiting for that, ‘When is that gonna happen?’ I’m sure Jordi’s going. ‘Man, everyone is saying it’ll happen.’ But they play so hard, it’s eventually going to happen with their talent.”

The Nets — without Nic Claxton and Egor Dëmin — played hard, and put some of the young talent on display.

It just wasn’t enough against a Cavs team that was better, even without Donovan Mitchell.

The loss pulled Brooklyn (15-45) within 1 ½ games of Sacramento, and just a half-game behind Indiana.

Michael Porter Jr. had a game-high 26 points.

Danny Wolf had a career-high 23 points, nine rebounds, five assists and two steals.

Nolan Traore scored 17 and Grant Nelson added 11 points, four boards and three blocks.

All three of the latter are rookies.

“I hate saying you can learn from a loss because it stings and it sucks, and losing as a competitor is one of the worst feelings,” said Wolf. “But with such a young group, the resilience of the fight when you lose to a team by four that you lost by 40 a week ago — speaks volumes to improvement.”

After getting hammered 112-84 by this same Cavs team on Feb. 19 coming out of the All-Star break, Sunday was a vast improvement.

Just as it was from Friday’s defensive humiliation in Boston when they let the Celtics put up the highest effective field goal percentage in history (80.8 percent).

But former Nets James Harden (22 points, nine rebounds, eight assists) and Jarrett Allen (20 points) were too much for their old team.

Brooklyn was down by a bucket in the waning seconds when Wolf intentionally missed a free throw.

But he threw it too hard off the glass, and the Cavs got possession to close it out at the free-throw line.

“I think it’s harder to miss the way I missed it than it is to make it,” Wolf said wryly. “I don’t know if it was the first time I’ve ever done that in my career. My thought process was to hit the front of the rim. Threw it definitely a little bit too hard. You live and you learn, something new that I know that I need to work on, that I didn’t know before.”

After falling behind 16-5 early, Brooklyn rallied.

Still down 36-29 with 9:45 left in the half, the Nets went on an extended 21-7 run to flip a seven-point deficit into a seven-point cushion.

Traore’s short jumper put Brooklyn up 50-43 with a minute left before the break.

The Nets were still up 62-55 after Porter Jr. found Noah Clowney for a layup.

They coughed up a 15-2 Cavs blitz, capped by Harden’s free throw.

The fourth quarter was tooth and nail.

Josh Minott’s 3-pointer put Brooklyn up 80-78 with 9:59 to play.

But they conceded an 18-8 run over the next six minutes and never regained the lead.

Allen’s layup left his former team in a 96-88 hole.

Brooklyn clawed within a point on Wolf’s free throws with 9.2 seconds remaining.

But Schröder sank two on the other end to put the Nets back where they were.

With 5.9 seconds left, Wolf made a free throw and purposely missed the second, but bounced it off the backboard to give away possession down 104-102.

Brooklyn got the break they needed when they fouled Schröder and he missed the second free throw; but Day’Ron Sharpe couldn’t fend off Evan Mobley for the rebound, and the Cavs big man sealed it.