If Tuesday’s clash with the Warriors was a measuring-stick game, the Nets are going to have to face some hard truths about just how short they come up.

The Nets got routed 117-99 before a sellout crowd of 17,732 at Barclays Center. And after underwhelming this season against the league’s better teams, they got outright thrashed by the best.

The Nets looked stagnant in shooting just 39.1 percent. They saw the Warriors torch them for 51.9 percent shooting behind Steph Curry’s 37 points. And in the end they trailed by 28 on their home floor in their latest test against the NBA’s elite.

“Well, I just don’t think we’re in that category yet. We’ve got a lot of work to do,” Steve Nash said. “We’re trying to improve as a group, get better and hopefully we can find a way to overcome some of our deficiencies by the end of the year.

“It takes time. We started the year with a continuity plan from last year that got thrown out the window obviously when Kyrie [Irving] didn’t come back, so we’re trying to build and figure it out. … [It] was a great lesson for us that we got to double down on some of our principles when the going gets tough.”

The going got tough in the third quarter, and the Nets rolled over.

Brooklyn got outscored 35-18 in that implosion, falling into isolation ball against Golden State’s box-and-one and triangle-and-two, shooting just 5 of 22. Against his old team, Kevin Durant — who was 6 of 19 in a rare off night — missed all eight of his shots in the third quarter, when the game got out of hand.

“They played great defense, they’ve got long defenders and guys that can help, sending bodies all the time when I had the ball,” Durant said. “And there’s some shots I wish I could have back. I rushed it. Once we got down 18 or 20, I was trying to get it back so fast and was taking bad shots and rushed shots.

“It’s all part of the journey and understanding what level you need to be at every possession. This was a great test for us.”

The Nets have repeatedly failed tests this season against top teams. They are 8-1 against losing teams, but fell to just 2-4 versus foes at or above .500.

After opening the season with a 23-point loss to Milwaukee, and getting outscored 42-17 in the fourth quarter in Chicago, James Harden couldn’t disagree with Nash’s admission the Nets are not elite yet.

“The goal is to be the best team at the end of the season, in the postseason. That’s the goal. But [we’re] probably not. We’re probably nowhere near,” Harden said. “But it’s a long season for us to get better and we will continue to get better.”

Harden had a team-high 24 points, but just four assists and five turnovers.

Curry punished the Nets as they moved back from drop coverage to switching, and looked rusty doing it. He hit 9 of 14 from deep, at one point he dribbling two steps past midcourt, putting up a 3 and turning to stride back upcourt before it swished.

The Nets actually led 25-16 after Patty Mills — filling in for the injured Joe Harris — found Bruce Brown for a 3. They were still up 58-57 after DeAndre’ Bembry’s layup with 33 seconds left in the first half.

But the Nets surrendered a 14-0 run spanning the break that eventually broke them.

Consecutive 3s by Andrew Wiggins (19 points) in the final minute of the first half started it, and back-to-back buckets by Curry ended it. Brooklyn trailed 71-58, and it just got worse.

Andre Iguodala’s running 3 over Durant made it 95-76 after three quarters, and the deficit hit 28 in the fourth.

Curry admitted the Warriors were fired up to not just bounce back from a loss but to face Durant’s Nets.

“It’s not the playoffs, but it’s an intensity where you know you have to show up if you’re going to beat a team like [them],” Curry said. “You definitely lock in, get focused and thrive off that competitive atmosphere knowing there’s a lot of talent in the floor.”