Brook Lopez has seen a record-setting 0-18 season start. He has seen the Nets assemble a squad they thought championship-worthy. He has seen his share of ups and downs with the Nets.

“I’ve only been in the league eight years, but I’ve seen a lot of different things in that time,” Lopez said. “Crazy stuff.”

But Lopez admitted he hasn’t seen anything quite like this Nets offseason.

Lopez is surrounded every day by Nets, mostly young players, who work out and condition under the direction of the team’s newly formed athletic performance department, overseen by Zach Weatherford who helped train Navy SEALS. That can come in handy if you’re playing overtime or hunting down bin Laden cronies.

Lopez trains amid rookies, returning teammates and free-agent signees, some he helped recruit after sitting with team brass in free-agency meetings. That’s new, too. He never did that before.

“I called guys, texted guys, met guys. Isn’t that amazing?” asked Lopez, who reverted to his self-deprecating humor. “They said, ‘Let’s send the most antisocial guy we have to recruit …’”

It exemplifies a new culture and approach around the Nets under new general manager Sean Marks and new head coach Kenny Atkinson. Lopez has seen and heard all this before in his Nets run; this is, after all, his ninth head coach (name them all, win valuable prizes). One difference: The training, by choice, started for many within two weeks of last season’s end. Lopez has been doing it for two months. Never before was he around this early.

“It’s abnormal,” he said. “It’s a good feeling. I know they’ve been harping on the culture and all but it’s a completely unique feel this time, like we’re moving in that right direction. It’s something people actually want to be a part of.”

The 7-foot, 28-year-old center calls the training staff “an international work force” with “guys taking what they’ve learned all around the world, bringing it together in this eclectic fashion so we really have the best of the best.

“It’s hard,” Lopez said. “We’re together and we’re doing it. Before, we’d have guys coming in, wouldn’t really get their treatment [or] their mobilization. And they weren’t necessarily on time. It’s the way it should be now.”

The Nets only won 21 games last year and surrendered their lottery pick because of the disastrous Kevin Garnett and Paul Pierce trade, which also will allow the Celtics to swap picks in 2017 and claim the Nets’ first-rounder in 2018. Lopez, ever the optimist, found a silver lining.

“Sometimes, obviously it’s an incentive to tank if you have the opportunity to get those high draft picks,” he said. “We don’t have that. We have guys who just want to win.”

Wait until the lads in marketing get that one: “The Nets: We Don’t Tank.”

Maybe it is not an Olympic-caliber roster, but the Nets signed a collection of proven NBA players and gambled (but lost) on two offer sheets. Lopez stressed his infatuation with the revamped roster that is dotted with hungry, high-character types, most of whom chose Brooklyn. There are 15 guaranteed contracts with 10 new faces. Lopez has played 487 Nets games. The four returnees not named Lopez — Bojan Boganovic (157), Rondae Hollis-Jefferson (29), Sean Kilpatrick (31) and Chris McCullough (24) — have played a combined 241.

The newcomers intrigue. There are veterans such as forward Luis Scola, guard Greivis Vasquez, guard Jeremy Lin, guard Randy Foye and blue-collar forward Trevor Booker. There are young guys with stuff to prove: guard Joe Harris, center Justin Hamilton and an intriguing player, Anthony Bennett, the slimmed down former No. 1 pick forward determined to shed the “draft bust” label. The Nets dealt proven pro Thaddeus Young for draft pick Caris LeVert, who plunged from the lottery through injury.

The Nets barely glanced at the Kevin Durants and Michael Conleys of free agency. They made impressive offers for restricted guys Tyler Johnson of Miami (four years, $50 million) and Allen Crabbe of Portland (four years, $75 million). Some thought them crazy, but both offers were matched.

“Obviously, someone other than us thought they were worth it,” said Lopez.

Some label Lopez a former All-Star trapped in another rebuilding project. He and the Nets wave off “rebuild” for a different word: “develop.” Atkinson, by all accounts, is the perfect choice. Lin had his best run with the Knicks when Atkinson was on staff. Lopez loves him.

“High basketball IQ, great players’ coach, huge on the team aspect but also getting individual players to commit to reaching their potential … [by] being on the floor with them and getting the work in with them,” Lopez said. “I’ve never seen another coach out there getting shots up, rebounding, running around, really in the trenches with the guys working like he does. I can see why he has that player-development reputation.”

The development started in earnest shortly after the season. And that was something Lopez had never seen previously as a Net.