Brian Lewis reports that the Nets have given Sean Marks an extension, just as they are extending Kenny Atkinson and his staff.

The Nets have locked up general manager Sean Marks with a contract extension, multiple sources told The Post. And playoffs or no, they already have seen enough out of Marks to want him to continue running the ship. While Atkinson has become a dark horse for NBA Coach of the Year, Marks has drawn praise for taking over a team that was not only 21-61 prior to his first full season, but also bereft of its own picks, and managing to get them in position to make the playoffs in just three years.

No specifics on how long the extension or how much Marks will be paid under its terms.

Sources had speculated in past few days that Marks was the “decision-maker” on the coaching extensions, indicating that he, too, had been extended. One source. in fact, told NetsDaily that other teams were “sniffing around” Marks if he was to become available.

Lewis quoted Atkinson Wednesday on Marks’ support for him.

“From Day 1 to right now … they have an understanding what this project is about and the necessary building blocks we’ve put in place, I think the patience of ownership has been outstanding,” Atkinson said. “Obviously me and Sean have a great relationship. And then the fans, that’s part of it too, to me. They’ve been beyond understanding.

“Even in that first year I was always shocked at how many people [said] ‘Hey, you’re moving in the right direction, you’re doing the right thing.’ Last year too, 28 wins and the support was always positive from the fans. So that’s huge. That gets you through the tough times. That’s why it’d be awesome to reward them with a playoff bid, quite honestly, to reward the franchise and the fans for their patience.”

Now, with their GM and coaching staff under contract, the Nets will have two key elements needed for the pursuit of free agents: a stable front office and a stable staff.

Marks has been credited with finding gems both in the late first and even second round of the Draft — players like Caris LeVert, Jarrett Allen and Rodions Kurucs— as well as rescuing others like D’Angelo Russell, his first All-Star, DeMarre Carroll, Joe Harris and Spencer Dinwiddie.

In addition, the two-time NBA champion —once as a player, once as an assistant coach— has built the Nets staff, starting with Atkinson but also including an extensive performance team.

Marks and Atkinson were reportedly given four-year deals in 2016, three years guaranteed with a fourth year team option.