Michael Porter Jr. likely has suffered — and overcome — more back injuries than any player in the NBA.

But Friday, the talent-starved Nets got a good look at their offense with Porter sidelined by fresh back woes.

It wasn’t pretty.

The shorthanded Nets struggled through an ugly 115-103 NBA Cup loss to the visiting 76ers before a sellout crowd of 17,809 at Barclays Center.

Already without Cam Thomas, the Nets played sans Porter, sidelined by low back tightness.

Egor Dёmin drives to the basket during the Nets’ Nov. 28 loss to the 76ers. IMAGN IMAGES via Reuters Connect

They can downplay it all they want, but it will set off alarms when Porter is sidelined with such a familiar issue.

The way they looked Friday will raise more alarms.

The Nets shot 40.5 percent, and just 13 of 43 from deep.

Trailing 42-31 after a Terance Mann jumper, the Nets allowed a 12-2 run as the game slipped away.

The Nets suffered through a six-minute drought without a basket that spanned intermission, from 4:42 left in the second quarter through 10:42 of the third when Mann scored.

Egor Dëmin was one of the few bright spots.

The rookie poured in a career-high 23 points with nine rebounds and five assists — with 15 points and four boards in the fourth quarter as the Nets furiously tried to rally.

Paul George attempts a shot during the Nets’ loss to the 76ers on Nov. 28. NBAE via Getty Images

But after trailing by as many as 21, their inability to score had dug too deep a hole.

The offense looked toothless without Porter, and his status for Saturday’s tilt in Milwaukee very much is in doubt.

“Obviously, we’re never going to rush him. His health, body, is the No. 1 priority,” Nets coach Jordi Fernández said beforehand. “We’re not concerned. [It’s] tightness, and we’ll see how he feels, and then we’ll give an update after the game.”

Porter actually has been something of an iron man, entering Friday leading the Nets in both total and average minutes.

He’d led Denver in starts the past two years as well, all the more impressive considering his history of back issues.

After herniated discs and a third back surgery in December 2021, Porter has been left with damage to the peroneal nerve, and needed a brace for “foot drop.”

Nontraditional means have helped Porter get past the injury woes, but back tightness actually cropped up earlier this week.

Porter suffered through arguably his worst performance as a Net in Monday’s loss to the rival Knicks.

Tyrese Maxey drives with the ball during the 76ers’ win over the Nets on Nov. 28. IMAGN IMAGES via Reuters Connect

He finished with 16 points for a minus-21, shooting 6 of 15 and an uncharacteristic 1 of 9 from deep.

Fernández acknowledged the back issue cropped up in that defeat.

“He felt tightness,” said Fernández, who spent four years with Porter in Denver as a Nuggets assistant. “As you know, Michael is a player that’s fought through everything in his career, and you got to give him credit for what he’s gone through and at the level he’s played. I don’t know if that’s the reason why [he shot poorly].

“I give him credit because he always wants to be there for his teammates. The good thing with Mike is, if he goes 1-for-9 one game, I think the next game he’s going to go 9-for-9 because, at the end of the day, it evens out. Every time he shoots it, I think it’s going in. So, even right there that he was not making shots, I don’t know exactly the reason, but I thought every shot was going in.”

Follow all the basketball buzz in Brooklyn

Sign up for Inside the Nets by Brian Lewis, exclusively on Sports+.

Thank you

Porter is averaging 24.3 points and 7.4 rebounds, both career bests.

With Cam Thomas sidelined by a hamstring issue, Porter has been the Nets’ offensive focal point and would be sorely missed if he’s out for an extended time.

“It’s tough. Being without Mike is definitely going to be tough,” Nic Claxton said. “He does a lot for us, especially on the offensive side of the basketball. He just causes so much attention. And he can get a shot off whenever. So, it’s going to be a collective effort.”

Elsewhere, in a clash of the league’s only two-win teams, the Pacers (3-16) beat the Wizards (2-16).

That left the Nets (3-15) in fourth in the lottery standings but now essentially just a half-game behind Indiana and New Orleans — whose pick belongs to Atlanta.