PORTLAND, Ore. — If Knicks rookie RJ Barrett has noticed anything different about interim coach Mike Miller, it’s a new defensive focus with a strategy of less switching on pick-and-rolls.

Miller staged a two-hour practice Monday at the Nike campus in nearby Beaverton, installing a few more new things. The Knicks will play their second game since David Fizdale was fired as coach, beginning their four-game Western trip against the Trail Blazers.

“He’s a different guy — of course it’s going to be a little different,’’ Barrett said. “[We’re] trying to lock in on the defensive end. [We’re] trying to fight through picks and try not to give up anything easy. It’s two different kind of styles, two different ways of coaching.”

Miller’s buzzword is bringing more “consistency’’ to the Knicks, who have a 4-19 record and are riding a nine-game losing streak. Fizdale was canned Friday with an eight-game skid and a 3-point defense that ranked second-worst in the NBA.

Miller, whose much less garrulous than Fizdale, said he’s tried to just be basic.

“We were working on the things that we need to do and really get a good feel, continue to work with our consistency of how we play possession to possession,’’ Miller said. “That’s what our focus is. These guys are pros. These guys have been great. We’ve really started in real simple terms that we want to be better at what we’re doing every possession, really getting to those things and sticking to it. Not worried about a big broad range of things. Let’s lock in these areas where we’ve shown we can be pretty good. Let’s do it for longer stretches.”

Knicks president Steve Mills and general manager Scott Perry, who attended practice along with player developmental guru Craig Robinson, had harped on “consistent effort’’ when they staged their Nov. 10 press conference that turned into Fizdale’s death knell. Fizdale’s Knicks career ended with back-to-back blowout losses to Milwaukee and Denver during which the club was beaten by a combined 81 points.

Miller also said moving the ball — a Fizdale theme — is high on the agenda.

“I think every team is searching for that,’’ Miller said. “It just creates different things within the offense. It doesn’t matter really what you’re doing. It’s more of the concept. It’s not what we’re doing, how we’re doing it. When the ball moves it improves everything.”

Barrett, whose shooting percentage had dipped to 40 percent after a strong start, said the club has done well in moving on from Fizdale. The Knicks lost 104-103 to Indiana on Saturday in Miller’s debut when the defense was stalwart.

“It’s tough,’’ Barrett said. “We responded great the other night in the game. Played a real good game except at the end. This is a business. We’re pros. Stuff will happen. We have a whole season to go and move on.”

The Knicks practiced at the Coach K Gym on the Nike campus, where a giant statue of Duke coach Mike Krzyzewski greets the players upon entering.

Barrett the Duke phenom, had seen it before.

“I’ve already been here before, nothing new,’’ Barrett said. Barrett and Ignas Brazdeikis practiced here when they played in the Hoop Summit for Canada in April 2018.

Miller said he’d stick with the same starting lineup with Frank Ntilikina at point guard, but admitted Elfrid Payton could finish.

Struggling Julius Randle (18 points) had a much-improved two-way game against the Pacers despite missing that last-second free throw.

“I think he has really, really played well,’’ Miller said. “I couldn’t even — how many games we go back — he’s been really effective and played really well. Really excited for him how he played on Saturday. Loved the energy in the plays, all the different things he did. I thought he played really well.”

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