LAS VEGAS — When it was over Sunday night, Suns players basked in their overtime victory over the Knicks. They privately made comments about how much easier it was to guard the much-hyped 6-foot-7 sniper RJ Barrett than they thought, according to an NBA source.

The Suns made Barrett look bad — just as the Pelicans did. The common refrain is summer league is not to be taken too seriously, but the Knicks have usually seen their recent lottery picks shine in this spotlight.

Kristaps Porzingis looked solid in 2015, Kevin Knox was terrific last July. And Frank Ntilikina sat out with a sore knee in 2017 — a bellwether to his marred young career.

According to sources, some members of the Knicks’ staff held concern about Barrett’s ability to translate his offensive game to the NBA because he relied so much on driving the ball. However, GM Scott Perry was always all-in on a player who last July was being heralded as the No. 1 pick for the 2019 draft.

In two games, Barrett has shot 7 of 33 — 2 of 13 from 3-point land. If Barrett can’t get to the basket with the same grace as at Duke, then clearly his 3-point shooting will need to improve. The lefty No. 3 pick from Canada was a 30.8 percent 3-point shooter with the Blue Devils while averaging 22.6 points.

One NBA personnel director told The Post his wariness of Barrett before the draft is coming to fruition in Las Vegas. Barrett, 19, gets another go at it Tuesday against his hometown Raptors at 9 p.m. at the Thomas & Mack Center.

“The concern was if he’d be able to get around guys in the NBA,’’ the personnel director said. “And if he didn’t, he’d use his shoulder (to get space) and the weakside (defense) would come on him fast. The weakside comes fast in the NBA. So if he’s not getting by guys, he’d have to become a better 3-point shooter.”

That can happen with hard work, but Barrett also has an intangible that the personnel director likes.

“The good thing is he has a lot of swagger and really believes in himself, and that’s going to help him,’’ he said. “Maybe it’s just time, but you expect more right away from a No. 3 pick.”

Knicks summer league coach Jud Buechler says he’s not worried about Barrett’s shooting and praised his defense with a late block vs. Phoenix and 10 rebounds.

The Knicks are looking to make things easier for Barrett and he’s been working at point forward to get the ball in his hands more. Against Phoenix, he played off on the wing.

Barrett has committed eight turnovers in two games and has shot 1 of 4 from the free-throw line in each game.

“It’s summer league, but there’s a lot of hype and pressure around RJ,” said another NBA scout. “He’s talented, but seems to be pressing. Shooting is his big issue and many factors go into a guy making shots, especially getting used to a new team and new level. At Duke, he was not efficient. That will be his challenge — efficiency. He will be at first a streaky shooter and efficiency should follow. He’s talented, but there’s no guarantees when his efficiency will kick in and how high a level.’’

It’s probably no time to panic, but former Knicks coach Jeff Van Gundy’s old mantra is this: If a rookie draft pick dominates summer league, it may mean nothing. If a player doesn’t shine at summer league, it is a concern. Perry and Knicks president Steve Mills watched the Phoenix game stone-faced from their courtside seats.

Van Gundy was Knicks head coach in 1999 for the infamous Frederic Weis summer-league fiasco when the rookie first-round pick’s poor play elicited a front-page headline in The Post: “French Toast.’’ The center never played a single game in the NBA.

“RJ should be just fine,’’ said another NBA personnel man. “Just let’s pump the brakes and be patient. What he’s going through right now will help him come October.’’

Buechler said after the Suns’ loss, “The shooting will come — we’re not worried about that. We’re telling him to stay aggressive, and as you can tell, he’s not backing away at all. He believes in it. We believe in it and it will come’’