Keon Johnson’s ‘maturing as a player’ already evident to Nets in NBA Summer League

LAS VEGAS — To get his contract, Keon Johnson has had to get out of the mindset of trying to get his.

The young wing has matured from his rookie season in Portland, when current Brooklyn assistant Steve Hetzel first coached him.

He’s matured even more since last season with the Nets, most of it spent in the G-League.

Friday’s under-control performance — complete with a tough game-winner — was proof that maturation is still ongoing.

And a great step for an unrestricted free agent trying to earn another contract with Brooklyn.

“Happy. I’m very happy. It’s growth; he’s maturing as a player,” said Hetzel, a Nets assistant serving as head coach for Las Vegas Summer League. “The game is slowing down for him, which is allowing him to slow down on the court and he’s making these positive plays.”

Johnson had 16 points and six assists in Friday’s 97-95 summer league-opening victory over Indiana, including a contested baseline turnaround to win it.

But that maturation has been evident in other ways, including Johnson’s willingness to defend and do the dirty work.

He’s uber-athletic, yet is learning to not only play more under control but to fit into a team concept offensively.

“In Long Island, he had stretches where he was in a mindset of, ‘I’m trying to get mine.’ That’s where he’s progressed the most, is trying to make the right play more than just score,” said Noah Clowney, who played alongside Johnson in the G-League.

“And you watch the game [Friday], he tried to make a lot of the right plays, and then being the best defender on the team. You’ve got to be one of the best defenders if you want to play. If you want to play, you want to get minutes, you’ve got to defend.”

Johnson did that, grabbing five rebounds, blocking three shots and coming up with a couple of steals.

Pairing better defense with his athletic gifts on offense is something that both Hetzel and head coach Jordi Fernandez have harped on.

“For me, [Fernandez] is always kind of reiterating being a dog on defense,” Johnson said. “Coming in and just playing with physicality. … He sent me little tidbits from our practices and that we’ve got to get better at certain little things. I feel like we’ve shown that here in the summer league thus far.”

Said Jalen Wilson: “He was aggressive but under control. With his speed, being able to elevate when he can, there’s so many different moves to make. His mindset coming in, picking up dudes 94 feet and on the opposite end getting to the cup, making tough shots like the game-winning shot he had. His mindset’s been great.”

The winner was a tough 12-footer on the baseline.

The contest was good, but the execution was better.

Johnson — signed on a two-way deal last season — made just five cameos for Brooklyn.

But he showed offensive flashes with Long Island, averaging 18.2 points, 6.4 rebounds on .478/.379/.803 shooting splits in 26 G-League games.

Johnson averaged 16.7 points in 15 more Showcase Cup games.

“I feel like it’s getting a little bit slower for me, but I feel like I’m starting to put myself in better positions where I can show what I can do with the ball in my hands and also playing off the ball,” Johnson said. “Each day this summer, I’ve been constantly getting better at playing off the ball and just playing with space. And here in the summer league, I’ll be able to show that a lot.”

He hopes enough to earn a return to Brooklyn, two-way or otherwise.

“Right now I’m just really focused on summer league. This is the only opportunity that I know I have right now,” Johnson said. “So I’m just really focused on playing summer league and just showing what I can do. And hopefully I’ll be here. But just giving myself the best opportunity for my career.”

The Nets aren’t expected to add to their front office.

But BJ Johnson — who has run the draft as director of player evaluation — is among several execs expected to get internal promotions, a source told The Post.