The Nets’ Kevin Durant-Kyrie Irving era officially ended Thursday night, along with their title hopes.

General manager Sean Marks had no choice but to acknowledge how difficult it was to trade Durant in the wee hours Thursday morning, and that — as the Nets entered a rebuilding process — their grand experiment simply hadn’t panned out.

“Look, I’m not going to sugarcoat it. It’s always difficult when you’re trading a player of that stature and that ilk; very difficult,” Marks said before the Nets’ 116-105 win over the Bulls. “My job as a GM and our job as a front office is to try and bring in that caliber of talent and so forth. So those decisions are not easy.”

No amount of sugar could make this pill any less bitter or easier to swallow.

When the Nets added Durant and Irving in June 2019, championships became the goal. When they traded for James Harden to form arguably the most offensively potent Big 3 in NBA history, titles became a fait accompli.

Except fate didn’t agree. Bad luck, bad chemistry, bad coaching, bad whatever, that trio played just 16 games together — ironically their last coming against Chicago, also Thursday night’s foe.

Harden forced a trade last Feb. 10, then Irving demanded one last Friday, bringing back Spencer Dinwiddie and Dorian Finney-Smith. Durant followed, with his trade to Phoenix ending the superteam that never was.

“I don’t think you have any regrets because you go all-in on a championship,” Dinwiddie said. “And if you look at the year where everybody was healthy with how dominant we were in the first couple games, the optimism that we had a chance and then even with the Harden trade you would’ve said there was a chance. Obviously KD stepped on the line, so some things in life don’t work out.”

Said Marks: “I look at it internally and say as well, it didn’t work. Let’s be honest there. We did not reach the full potential of where we thought we’d could get to, our hopes and honestly beliefs.

“So, it didn’t work. Some of that is through things we can control, some through things that we can’t control. But the end of the day, now we’re focused on this pathway right now.”

That pathway is a rebuild, moving Durant for Mikal Bridges, Cam Johnson, four first-round picks, a 2028 pick swap, and a couple of second-round picks.

It’s an improved version of the package the teams discussed after Durant put in his summer trade request. At that point, Marks and team owner Joe Tsai convinced Durant to stay. But this time he wouldn’t be swayed, presumably pushed over the edge by the Irving deal.

“These are discussions between Kevin, myself, Joe, Rich [Kleiman, Durant’s manager],” Marks said. “These are ongoing discussions behind closed doors, but they’re honest discussions. We don’t always agree on everything, that’s not what it’s always about. But … we felt that this was the right time.

“There’s a limit, right? You can certainly try and convince guys and you put your best foot forward and say here’s what the roster looks like, here’s what we’re trying to do. But at the end of the day, this works out for all parties included.”

It was a deal that the Nets felt would keep them the most competitive. But having to move Durant — and shut their championship window — had Marks sad, mad and tons of other emotions all at once.

“I was sad. … You do everything you possibly can to put together a team that you can be proud of and say we can be in that championship conversation,” Marks said.

“Don’t think I really saw it coming,” Joe Harris said. “But we talked about it after the game the other night where the trade deadline is a lot of unexpected things happen, especially here over the last couple of years.”

Marks praised Bridges and Johnson, and noted the Nets have far more picks to rebuild with than when he arrived. He talked around the Irving trade, and about how the guard had said he felt “disrespected” in Brooklyn and had been plotting his exit after Year 1.

“When you get to a point like we are now and it didn’t work, we weren’t the last team standing … it’s easy to go and say, this, that or the other, whether it’s pointing fingers or what have you,” Marks said. “We have to internally look at did we do everything we could have? Could we have done more? Sure. But that’s on everybody.”