Nets rookie Rodions Kurucs has been the steal of the second round, and he poured in a career-high-tying 24 points in Monday’s loss in Boston.

But dig deeper — Nets coach Kenny Atkinson didn’t see all the 3-pointers Kurucs had, but rather all the rebounds and defensive stops he didn’t.

When asked after the game to assess Kurucs’ performance, Atkinson’s grimace told the story. And his reply elaborated on it.

“Well, I want him to get back to defending and rebounding,” Atkinson said.

Kurucs, a 20-year-old Latvian, has shown an encouraging tendency to be at his best against the best. After scoring 24 points against Indiana, he matched that Monday against the Celtics, shooting 8-of-13 from the floor and 5-of-7 from deep.

He’s just the fifth rookie in team history to hit five or more 3-pointers — Bojan Bogdanovic, Ryan Anderson, Kerry Kittles (twice) and Chris Morris (twice) — and he has twice as many 20-point games as all other 2018 second-round picks combined. Still, the Nets need more from him than shooting.

Kurucs grabbed just one board Monday, didn’t notch a single steal, and didn’t provide the defensive energy the Nets have come to expect from him.

“One rebound [Monday], no steals; that’s got to be his role,” Atkinson said. “I’m thrilled he made those 3s, I’m thrilled he was good offensively; but his role on this team has to be [a] rebounding and energy guy, defending. But good offensive game.”

Once Allen Crabbe went down with a knee injury, Kurucs started the past 13 straight games. He’s averaged 10.9 points and shooting 47.2 percent from the floor, 38.6 percent from deep and 89.3 percent from the free-throw line.

With the Nets 15-10 in games Kurucs has played — and 9-4 in those he’s started — he has a golden opportunity to Wally Pipp the injured Crabbe. But only if gets back to doing all the little things on defense that so impressed the coaches in camp.

That includes using his 6-foot-9 height and over 7-foot wingspan to harass shooters, tip away passes and come up with steals and rebounds.

“I understand that I have to go for the rebound sometimes and help them out,” Kurucs said. “I’ll just try to do that next game.”

Kurucs grabbed 42 rebounds and notched five steals in his first seven starts, a plus-21 thanks to his high-energy play. But after posting back-to-back double-doubles in home victories over Phoenix and Charlotte, his activity has waned. Kurucs has just 13 boards and two steals in his last six, a minus-30 over that span.

He was a minus-22 in Charlotte and a minus-17 at Memphis, acknowledging that Atkinson had given him the message about getting back to what he’s good at, and more important, back to what the Nets need from him. And the message was received.

“Yes, [he talked to me about it],” Kurucs said. “Now I think my strongest parts are to play defense to get the rebounds and to fight for every ball. And the offense, it just comes. That’s all part of my game now.”

Once Kurucs gets back to that, he’ll get back to being the steal of the second round. The Nets had him graded out as a first-round talent, and it’s easy to see why. Selected 40th, he’s 12th in his class in Win Shares and 19th in VORP (Value Over Replacement Player). He continued a strong history of drafting under general manager Sean Marks.

Second-year center Jarrett Allen was taken 22nd but is second in his class in Win Shares and fifth in VORP. Third-year wing Caris LeVert, who was selected 20th, has missed much of this season but is still 10th in Win Shares and sixth in VORP.