MILWAUKEE, Wis. — RJ Barrett doesn’t seem concerned, and neither does Tom Thibodeau.

Eventually, the Knicks’ fourth-year guard and his coach agreed, the 3-pointers will fall. They just aren’t dropping yet.

“Let it go. You’re open, shoot,” Thibodeau said after the Knicks’ 119-108 loss to the Bucks at Fiserv Forum, in which Barrett went just 1-for-7 on 3-point attempts to fall to 4-for-28 from beyond the arc this season. “The more he does it, the better he’s going to be. A lot of confidence in him.”

When Thibodeau was asked if the Knicks are asking more out of Barrett this year as their top perimeter defender compared to previous seasons, he snapped: “That’s comical.”

Barrett, who scored 20 points, had a more understated response when told he had entered Friday night having run an average of 2.76 miles per game and 1.31 miles on defense, according to NBA.com.

Both are among the top figures in the league — he was seventh in the first stat and fifth in the second — an example of just how much energy Barrett expends on a game-by-game basis. But he won’t attribute his shooting woes to all those miles logged thus far.

“I feel like I was guarding people last year, ended up doing pretty well, finding [my] rhythm,” he said. “I definitely could be playing better offensively and I feel my rhythm coming back after not playing for a while. But my rhythm [is] coming back slowly every game so I’ll be alright.”

The Knicks really have no other choice but to depend on Barrett as their perimeter defensive stopper, particularly because their next best wing defender, Quentin Grimes, is still out with a nagging sore left foot.

When the Knicks let Reggie Bullock walk prior to last season, opting for Evan Fournier’s offense instead, Barrett became the guy on the defensive end. As Barrett said, his shot came around last year, when he averaged a career-best 20 points per game. He expects the same to happen this season.

Thibodeau has watched Barrett put in the extra work at night, and is certain those reps will pay off soon. So does Barrett.

“I’ve been in the gym, I’m going to keep being in the gym. It’s going to happen,” Barrett said. “I’m not worried about it.”