Memo to Phil Jackson: Kristaps Porzingis is getting stronger, putting on weight and “obsessed’’ with his offseason training. However, the 7-foot-3 Latvian for whom the Knicks president is listening to trade offers gave a lukewarm endorsement of the triangle offense, saying it hasn’t worked yet because the Knicks haven’t had the right players.

In an English-language interview Sunday with Latvian journalist Andrejs Silins of Sportacentrs.com — before a report broke Jackson has been receiving calls for Porzingis ahead of the draft — the Knicks power forward spoke a great deal about his offseason training. The Post has reported the Knicks have not dispatched a coach to Latvia to work with him, and instead he has hired a couple of New York-based physiotherapists.

“I enjoy the process of being obsessed,’’ Porzingis said in Barcelona, Spain, during an Adidas promotion. “It’s going well. I did a little bit of boxing. I’ve been doing swimming, running track, different stuff. That boxing and fighting was really tough for me. I really haven’t done anything like that. It’s good for cardio and wanted to learn how to punch.’’

At this point, Porzingis might feel more like a Knicks punching bag. Jackson stated after the season Porzingis was not untouchable, then he met with Arizona 7-footer Lauri Markkanen on Monday as a replacement option in case something pans out on the trade front, which appears unlikely.

The cold war has deepened. Porzingis posted an Instagram selfie Tuesday captioned with “fr’’ (for real) after the trade news leaked. He told The Post before leaving he did not want the Knicks to trade him.

Porzingis said in the Latvian interview that he works out twice a day.

“I’ve gained a little bit of weight – probably my legs are the strongest ever,’’ Porzingis said. “I’ve gained a lot of weight for the legs. I’m going to keep going until national team [training camp]. I’ll keep working as hard as I’m working until this moment. I’m ready for national team. I’ll be ready for the season.”

Porzingis has yet to speak to Jackson or GM Steve Mills since the season ended, after he caused a stir by blowing off his exit interview.

Part of his frustration is with the forever-changing scope of the offense, with Jackson recently going all-in again on the triangle.

“It is different,’’ Porzingis said in Spain. “It works if everyone believes in it, if everybody knows where to move and where to go and what to do and reads the situation well. You can’t do it with everybody. You have to have the right players, have to have players with sharp minds, that can read the game quickly and make the right cut and pass. I haven’t really been a part of a really good triangle team. We always had some trouble a bit. We’ll see what we do next season.’’

Porzingis admitted to frustration over his sophomore campaign, in which the Knicks recorded a 31-51 clip, and said the large expectations everyone had made matters worse.

“The first season was all positive,’’ Porzingis said. “Nobody expected anything from me, everybody was so happy and it went by quick. Next season was much tougher for me. Because much more attention was paid to me when I was playing, and the expectations were way higher. We didn’t come up to the expectations. We didn’t do it. In New York, you have to be ready for high expectations and have to be ready for the pressure that comes. We have to get better as a team to make the city happy.”

Porzingis said his first workout begins at 10 a.m., followed by one at night.

“The No. 1 thing is physicality,’’ Porzingis said. “I want to get stronger. Eighty-two-game season takes a lot from you. As the season goes, it’s hard to keep the weight up. It takes a lot for me. It decreased during the season.

“Basketball-wise, I’ve got to get better as a post player, need more moves to add to my game. I’ve watched a lot of film, analyzing things I can do better in the game. I have to put all that together, a lot of little details and moves I want to add to my game, it takes a lot of time. When you enjoy the most during the season is when one move you worked on comes out, but you have to find the joy in the process — if not, you lose motivation and won’t have same edge.”

Porzingis will join the Latvian National Team for the European Championships in late July. Knicks coach Jeff Hornacek said he would attend, but he may not work directly with Porzingis while there.

“Nobody from the Knicks will be there [working me out],” Porzingis said. “You see what happened to Josh Longstaff [the Knicks assistant whose contract was not renewed]. But I will have my physiotherapist.’’

The Knicks star reflected on his draft workouts from two years ago, when the Lakers passed on Porzingis at No. 2, as did the Sixers at No. 3.

“The first thing came to my mind was my Lakers workout,’’ Porzingis said. “It was the worst one, worst workout I ever had. I’d never had been so tired in my life. The draft process was a tough experience. A few teams interested — they were long, long workouts. I lost a lot of weight during the draft process, but it was a good feeling when you get drafted and drafted where I really wanted to be: New York.’’