Jamal Murray issued a challenge to his locker-room neighbor.

He needed to be entertained somehow. And someone other than Nikola Jokic was going to have to score to make up for Murray’s absence. He was recovering from a hamstring injury, and the Nuggets were halfway through a month of fending without him. It was Nov. 17, 2023, in New Orleans.

So Murray turned to Christian Braun in the visitors’ locker room. Take a step-back tonight, he dared the 22-year-old.

“I ended up hitting three 3s that game,” Braun told The Denver Post, accurately recalling the box score one year later.

Whether any of those 3s qualified as a legitimate step-back is open for debate. But Braun made 11 of 19 shots from the field that night, attacking the basket and unleashing jumpers with the confidence of a much older player. It was as if Murray had possessed him. His career-high 25 points revealed a momentary glimpse of scoring potential.

Braun hasn’t matched that yet, but it might only be a matter of time. Especially if Murray keeps challenging him to outdo himself — a trend that continued Wednesday night before Denver’s win over Oklahoma City. Braun has rocketed out of the gate as the Nuggets’ new fifth starter, averaging 16.6 points, 5.3 rebounds, a block and a steal per game through a tenth of the season.

“Let’s stop talking about comparing CB and KCP,” coach Michael Malone said Friday after Braun’s predecessor, Kentavious Caldwell-Pope, was invoked in a question. “I don’t even think it’s worthwhile anymore.”

When Caldwell-Pope signed with Orlando in free agency this summer, Braun earned the promotion with his defense. He’s vindicating it with a third-year leap on offense. In nine starts, he’s shooting 55.8% from the floor — nearly 10% higher than he did in a smaller role last season — and 50% from 3-point range at an increased volume of 3.6 attempts per game.

That’s where Murray comes in. His seat is next to Braun’s in the locker room at Ball Arena, but they post up next to each other on the road as well. Last season as Braun was turning around his shooting percentages, he cracked a joke to Murray that he was going to be a runoff jump-shooting threat soon. To Murray, it was hardly a joke. He has grown fond of instructing the younger guard on a nightly basis — usually nothing as specific as a step-back shot, but often a message involving assertiveness.

“ ‘Keep shooting the ball. Keep being aggressive. Get up more attempts,’ “ Braun told The Post. “Constantly. When he’s hurt. When he’s not playing. He’s, before the game, telling me he wants me to do this. During the game, he sees this. He’ll point it out. … It’s not just shooting. He wants to challenge me. ‘Hey, I want you to pick this guy up full court.’”

This week was another one of those times without Murray in the lineup. He was going through concussion protocol after sustaining a head injury Nov. 1 in Minnesota. But on Wednesday, before Denver hosted the undefeated Thunder, Murray still made time to light Braun’s fuse.

“Let’s see New Orleans CB,” Murray told him, according to Braun. “Let’s see that CB.”

Braun scored 24 points on 4-for-8 outside shooting, this time in a win. It was his second career 20-point game. Friday night against Miami was his third.

“Even his first year, he was really good when he went. In whatever he did,” Murray explained after Braun’s 21-point night on 7-of-9 shooting vs. the Heat. “Just being more decisive. Not just more decisive, but more confident in what he’s gonna do. If he’s gonna drive, he’s going. If he’s gonna shoot, he’s shooting. … It’s good to see him get it up and shoot with confidence. Even if he misses, the next one’s going up. He’s not thinking about it. If he’s open, he’s letting it fly. Obviously, his game is more getting to the rim and dunking on people, but he’s well-rounded.”

Braun is trying to model routines after what he observes Murray and Jokic doing. He surrounds himself with both. After sitting near Murray in the locker room, he often plants himself next to Jokic on the bench. He picks up on details that might help him manage the increased toll he’s facing, even after playing every game last year. Seeing Murray use hot packs to keep the knees and ankles warm at halftime helped inspire Braun to use them. “I have to,” he said. “At all times, to be honest. On the bench. When I first come out, I’ve gotta have one on my back.”

This is how Braun goes about learning to be an NBA starter: taking notes and accepting challenges.

Even nine games in, when the fit seems seamless, he understands the 82-game grind hasn’t truly tested him in his new role yet.

“I try not to think about it, to be honest,” he told The Post. “Whatever it is, you’ve gotta show up. And I think I learned this from Nikola. Ups, downs, hurt, feeling great, you’ve gotta show up and do the same work every single day. Establish a routine, and no matter how you feel, do that exact same routine. … So I don’t want to think about it. I don’t want to have lows or highs. I’m sure I’m gonna feel good some days. Some days, I’m not. That’s already happened. Because I’m still getting used to it. I’m still learning how to approach playing high minutes.”

So far, the KU alum is averaging 35.3 per game, up from 20.2 last year. These minutes are more strenuous, too. The Nuggets expect him to shoulder defensive responsibility for the best guard on the floor: Shai Gilgeous-Alexander, Anthony Edwards, perhaps Luka Doncic when the Mavericks visit on Sunday.

Resisting the instinct to make a beeline for the bench after halftime has taken some getting used to. It’s a reflex built up from the first two years of Braun’s career. For the first time, he has to be physically and mentally prepared the instant the game restarts.

“When Joker goes out (to warm up) at six minutes (left in halftime), he never misses that,” the guard said. “So one thing I learned: I had to go out there earlier. At halftime, I had to go out there earlier. I had to move around a little bit and stay warm. So there’s a lot of different things I’ve learned, and there’s a lot of things I’m gonna continue to learn throughout the year.”

In the meantime, Murray will stay in Braun’s ear about shooting. The right ear, to be exact.