Nothing comes easy in New York. Even for the Big Maple.

It not only takes big talent, it takes a big heart to have the courage to look inside yourself to make changes.

James Paxton had to make those changes, and now the Yankees need the left-hander to continue to do what he did when he reeled off 10 straight wins — and do it under the October spotlight, perhaps starting with Game 1 of the ALDS Friday night against the Twins at Yankee Stadium.

He opened the season 5-6 with a 4.72 ERA in his first 18 starts and went 10-0 with a 2.25 ERA in his last 10 starts, not counting the final one-inning start against the Rangers when he was taken out because of nerve irritation in his left glute.

“The biggest adjustment I made was just narrowing my focus to one game at a time, one pitch at a time, not looking too far ahead, and not worrying about what’s happened in the past,’’ Paxton told The Post. “Just focused on just really attacking the strike zone.’’

Too often pitchers try to make the perfect pitch and put that extra pressure on themselves. Trying to be perfect in any walk of life is difficult, but when you are on the mound trying to be perfect, you lose the creative aspect of challenging the hitter.

Then you often make a mistake in execution and location. Mistakes wind up in the seats.

To make that adjustment to narrow his focus, Paxton had to make a mental adjustment. He knew New York was going to be different than Seattle — but you never really know how different until you get here and feel the heartbeat of Yankee Stadium.

Paxton, 30, finished the season with a 15-6 mark and 3.83 ERA. He has always been one to rely on guidance from a mental-skills coach so now he brought this new set of circumstances to the table and explored how he could be better mentally prepared for this job.

“It’s definitely something I’ve dealt with in the past, but coming to a new team, new circumstances, I kind of had to go through it again and figure it out on this new team,’’ he said.

“I’m so excited,’’ he said of pitching October baseball. “I’ve never been a part of a postseason team, so to be going into the ALDS is going to be a lot of fun. We are going to have a great time playing the game of baseball.’’

That comment shows you how far he has come in his mental approach, not looking at this as something in which he has to be perfect but a situation to lean into, take it for what it is and enjoy each moment postseason baseball offers.

Think of it as fun, and it becomes that much less of a monumental task.

It all came together for Paxton once he freed up his mental approach along with freeing up his curveball. Hitters now sit frozen by his curveball because they have to dial it up to handle his fastball that breathes fire.

The urging of pitching coach Larry Rothschild made Paxton accept the curveball and now he has a complete understanding of what that pitch does for him.

Paxton made the adjustment in early August.

“It’s something that slows guys down because my other two pitches are hard, the fastball and the cutter, so it gets them off-balance a little bit and it makes them slow their swing down and respect something on the outer half,’’ Paxton said. “The curveball plays really well off my high fastball. It gives them that little hesitancy.’’

A little hesitancy goes a long way. Aaron Boone loves what he sees.

“I think his focus and conviction to what he is doing going into a game and during a game has been excellent,’’ Boone said. “He hasn’t been affected by anything going on during the game. He is coming in with the blinders on, knows exactly what he needs to do to execute, has the confidence in his ability to go out and do it. You can really see that within the game. He is very unemotional. Kind of a really good focus about him, a rhythm that he comes between innings, boom, he is locked in, what’s my next pitch I have to execute. He’s done a really good job.’’

Rothschild was able to get through to Paxton about not only the value of adding that curveball but also helped get his head straight by releasing some of the pressure of pitching in New York.

“You make him realize, it’s not just him,’’ Rothschild said. “It’s everybody. It’s a whole conglomeration of players. If we win, it’s going to be everybody. I know when you are starting a game in the playoffs you put a lot on yourself. If he just uses that energy and challenges it, he’ll be fine.’’

Narrow the focus. Think in the moment, not just about what happened. Stay locked in on the mound. Let your talent work.

Aaron Judge watched Paxton develop as the season progressed. Judge pointed to his chest, his heart, as he said, “I think the biggest thing is what he has showing in here. He’s always had ‘the stuff.’ Right when we first got him, I said, ‘Oh, this guy is an ace. He is the best left-handed pitcher in the game.’ Now I’m starting to see not only the stuff being there, but he is got it right here.’’

In his heart.

“Every single outing I see him get out there on the mound and you could just see he now knows he has that ability,’’ Judge added. “I can feel it on defense that he is going to go seven, eight innings strong. He is one of those pitchers where you feel we just have to get him one run. We get him that one run, this game is over with. That’s the biggest difference I’ve noticed. It’s not the stuff. He is going after guys. He knows he has good stuff and he is attacking hitters.

“I grew up with the Yankees, so I kind of knew the mentality, knew the pressure, the spotlight you get put under. Someone like Pax, he’s coming from the Mariners, and doesn’t really know what is going on in New York, he was a big trade piece, and everyone is expecting this and that. That’s a lot of things coming at you. From the media side, your friends’ side, it’s a new city, fans you’re trying to impress, then a slow start, that’s tough but he has shown that determination.

“I always see him talking to Larry and [bullpen coach Mike] Harkey on what do I need to work on. He’s always in the weight room so I knew eventually he was going to get to the Paxton that I knew he could be.’’

The James Paxton the Yankees are going to need throughout October, starting against the slugging Twins.