It was cold outside and lonely inside. As Peyton Watson got settled in Michigan last November, he was encountering new hurdles in every environment.

Watson was used to being the young pup on his basketball teams. The rookie who gets made fun of sometimes but has fun with it, because his default setting is lighthearted and laughing. In high school, he was the only freshman on varsity. After one of his team’s 6:30 a.m. conditioning workouts in Los Angeles, he was checking his phone, waiting to go to his first class of the day. An older teammate snuck up behind him and smacked his neck, giving him a scare.

“Everybody fell out laughing and was like, ‘His neck is spicy,’” Watson recalled. The nickname “Spice” stuck the rest of that season.

But ever a socialite, Watson was happy to be along for the ride. Maybe a small part of him preferred that to being just part of the pack on JV.

He was used to not playing a ton, also. It was the story of his pre-NBA career. Watson didn’t blossom into a star high school player until his junior year, when he hit a growth spurt and launched from 8.6 points per game to 23.8. Then the pandemic got in the way of his upperclassman seasons. Games were limited. He committed to UCLA and averaged only 12 minutes and 3.3 points his lone year of college ball, barely appearing off the bench before getting picked 30th overall by Denver in the 2022 draft.

He was used to being the life force of a locker room, if not a team’s life force on the court.

What he wasn’t used to was isolation — hence the challenge that Nuggets general manager Calvin Booth had issued for Watson before a crucial minor-league stay with the Grand Rapids Gold.

“He’s very, very outgoing,” said his high school coach, Shelton Diggs. “Very, very talkative.”

Off to the cold

A year later, Watson is still maturing as a player and person, but he already looks back on his G League season in Grand Rapids with a fondness and appreciation that was more difficult to keep in perspective at the time.

The 21-year-old is early in his second season with the Nuggets, now becoming a regular in Denver’s nine-man rotation. If coach Michael Malone has been tough on him, it’s because he and the Nuggets have soaring hopes for the Long Beach native.

That organizational faith in Watson’s development was evident to him and his family from the very beginning of his G League assignment in 2022 — even if it began with a tough pill to swallow.

Watson always had family around him while growing up. He fell in love with basketball by attending his uncle’s high school games as a toddler. Brantley Watson is only 15 years older than Peyton, as much an older brother as an uncle. They moved in together during Peyton’s year at UCLA, then Brantley moved to Denver to help out after Peyton got drafted.

After the team told Watson he would be spending significant time developing in the G League, the family started making arrangements to visit Grand Rapids one at a time throughout the season. Then Brantley got a call from Booth, the young GM who rolled the dice on Watson with a first-round pick.

“Brantley, don’t go,” Watson’s uncle recalls Booth telling him. “Let him fly to Grand Rapids, let him be in the cold, let him go to those practices, let him do it himself. And it’s gonna help him grow.”

“I was on board with it, just because I’ve gotta work on the things that I’m not used to doing,” Peyton told The Post. “And I’ve always had such a strong support system and family that I never really had to do those things.”

So off he went to Michigan, taking on his first year of professional basketball.

The Watsons stayed home.

The warm-up

He might not have understood what he was watching, but Watson was nonetheless transfixed.

He was 3 years old, a small speck in the crowd at Dominguez High School, where Brantley spent his senior year. Watson’s parents, Julio and Antoinette, took him to games to watch Julio’s younger brother. At a previous school, Brantley wore No. 34, so Peyton’s parents got him a baby-sized Paul Pierce No. 34 jersey to support his uncle.

At the new school, the pregame routine was just as much of an attraction as the game itself. Especially for impressionable young children. Dominguez had an elaborate warm-up that looked more like a choreographed interpretive dance performance. A basketball wasn’t introduced until after the warm-up, which focused on defensive movements. Four players would spring into action at a time. They did close-outs, synchronized zig-zagging defensive slides, handshakes with teammates along the baseline for panache.

The kid was hooked.

“Peyton found it very entertaining,” Julio said.

“He’s just sitting on someone’s lap, staring, googly eyed,” Brantley said. “It’s just one of those things that enthralls kids. You don’t really know why they’re so enthralled by it. I guess just the movement and the speed.”

Peyton, still young enough to have a vision of it in his head, thinks it was the comradery.

“Menacing warm-up routine,” he said. “Running side to side, sliding, slapping hands. It was super tough.”

Then the layup lines would start, and Peyton’s focus would drift away. The Watsons stayed to watch the games, but back home, Peyton wasn’t desperate to get his hands on a basketball to dribble and shoot. Instead, he was sliding around the house, or practicing defensive movements in front of a mirror.

“He would mimic the warm-up routine,” Julio said. “… Which is ironic, because he’s a great defender now.”

Since he was drafted, it’s been an adjustment for Peyton to think of himself as a defense-first player. But considering how formative the warm-up routine was, maybe this was meant to be. At Long Beach Poly High School, Diggs could feel himself levitating with his pupil every time Peyton left his feet to block a shot. “Gimme that (crap)!” Diggs would always shout, whether it was practice or a game. He still exclaims those same words when he watches Watson block a shot in the NBA.

The Nuggets have been giving Watson defensive comps to study since he arrived in the organization, including Mikal Bridges, Jaden McDaniels and Dorian Finney-Smith. The message is clear: With his wingspan and instinct, Watson can earn his minutes and money with defense.

“Unless you’re one of the best offensive players in the world, if you play for the Nuggets, you’re not one of the top five options,” Brantley said, reflecting on the mental adjustment. “You’re just not.”

FOMO

Seasonal fashion was never a necessity for Watson as a teenager. But Grand Rapids is far from Los Angeles. The G League quickly, forcibly introduced him to winter clothes.

“I’m a fashionable guy,” he said. “I like to wear nice clothes. But it immediately became comfortability over looks. You literally had to go out in a heavy jacket out there, or you were gonna freeze.”

Watson got a Moncler jacket and wore it religiously. He lived in a one-bedroom apartment in the affiliate’s community-style setup. He worked out with player development staff. In his free time, he did everything possible to avoid the frigid outdoors, finding shows on Netflix and HBO Max to binge. (When Watson went to Michael Porter Jr.’s birthday party at the Lake of the Ozarks the next summer, the cartel thriller series “Ozark” was in the back of his mind. “A little eerie vibe,” Watson said.)

The rookie’s No. 1 obstacle was “FOMO” — fear of missing out. Watson thrives on having good company, and he had gotten to know his new Nuggets teammates from working out with them in the summer and being around them at the start of the NBA season. He had found friends and mentors in the starting five. “He’s one of my funniest teammates that I’ve been around,” Kentavious Caldwell-Pope said.

Caldwell-Pope noticed Watson’s defensive potential early and tried to guide him, “just watching film with him, showing him what to look for in the film, and just teaching him ways on how to guard his man.”

For Watson, the move to Michigan initially was like being the freshman on the varsity team again, then getting sent to JV.

That also meant he had to readjust to the idea of being a primary scorer for the first time since those abbreviated high school seasons. It might’ve felt daunting at first, but it didn’t take long. He registered 21, 27, 32 and 28 points in his first four Gold games. But with the G League team so far away from headquarters in Colorado, Watson couldn’t escape the feeling that nobody was paying attention at first.

“It does kind of feel sometimes like I was separated from the pack,” he said. “Or like, I was missing out on what they were experiencing. But at the same time, they felt that I was gone, and they wanted to reach out to me and help me get through that.”

As Watson excelled, he got texts, calls and FaceTimes from Denver. Jamal Murray hit him up at one point. Team staff provided a steady flow of constructive feedback. Phone conversations with family preached patience, and slowly, Watson grew less antsy with the idea of developing in the minors. He embraced getting to know his new team. He embraced the independence.

“I just kind of wanted to prove to myself more than anybody that I could chill by myself, live by myself, take myself to my workout, be there on time,” Watson said. “Just be a professional.”

“Calvin was genius,” Brantley Watson said. “It did help (Peyton) to grow up. … I think it was a point for him where it could be either a good moment or a bad moment. He had to deal with it.”

Brantley and Peyton are back to being roommates this season in Denver. Julio and Antoinette are taking turns visiting. Watson is the Nuggets’ ultimate wild card prospect, the guy who barely played in college, a representation of the team’s ambitious vision for a draft-and-develop dynasty. If the Nuggets are right about him, it will have started with the phone call and those months in the cold.