David Fizdale and Julius Randle have repeatedly discussed the time it will take for the Knicks’ biggest offseason signing to adjust to his new and expanded role.

That period may last longer than many will like.

“To create and break habits, it takes two months of doing it consistently. That’s just science,” Fizdale said Saturday. “Right now, we’re nowhere near that point. But I still see him doing good things on film. I know he may get frustrated sometimes with himself, but at the same time we just gotta keep chopping that tree so he can get to that place.”

Though Randle is averaging a double-double (14.3 points, 11 rebounds), the 24-year-old power forward has failed to reproduce his promising 25-point, 11-rebound, one-turnover Knicks debut. In Friday night’s loss in Boston, Randle was limited to eight points while attempting just seven shots.

The career 50 percent shooter is hitting just 43.6 percent from the field, including 1 of 15 from 3-point range.

“Just getting Julius to not press, and to slow down and see the game and make easy plays, when he does that he’s really good,” Fizdale said. “The clips and the film we’re showing him right now are the ways he can make the game easier for himself and others.”

Randle, who has also been tasked with point forward responsibilities, has struggled in a playmaking role. Facing a constant barrage of double teams — more than Fizdale had anticipated — Randle has committed 27 turnovers over the past five games and ranks fifth in the league with 4.7 per game.

“I never expected [this]. He draws double and triple teams, and they’re really forcing him to have to trust,” Fizdale said. “I don’t know if he’s ever seen this before in his career. That’s a tough thing for a guy for the first time ever, seeing these kind of coverages. So, we just gotta make sure our spacing is right around him, and we’re ready to make shots when he’s kicking that ball out.”

Mitchell Robinson sprained his left ring finger on Friday night against the Celtics, and will wear a splint when he suits up for Sunday’s game against the Kings. … Dennis Smith Jr. (personal) and Elfrid Payton (hamstring) will be out again, and Fizdale still has no timetable on either point guard’s return.

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