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NEW YORK — The visiting locker room at Barclays Center had all the trappings of getaway day.

Locker room attendants scurried about, picking up socks and tape and sweaty compression shorts. Players dressed quickly and bundled up for the 7-degree arctic tundra whipping down Atlantic Avenue in Brooklyn, hoping to make the first bus out of the borough.

The Boston Celtics had just escaped Brooklyn with an 87-85 victory over the Nets on Saturday night, and now they were preparing to escape the continent, too—with the best record in the East. Galvanizing them in this feat of consistent excellence at roughly the midway point of the 2017-18 NBA season has been the offensive wizardry, leadership and defensive grunt work contributed by none other than Kyrie Irving.

Wait, did the words leadership, defense and Kyrie Irving just appear in the same sentence? This may take some getting used to, this new world in which LeBron James' one-time sidekick now has his own championship-contending team to run.

"We don't want to be most teams," Irving said in the locker room, explaining how the Celtics avoided the setup for a classic letdown game. Playing without Al Horford (sore left knee) and riding a five-game winning streak, it would've been easy to mail in this one-off road trip to frigid Brooklyn and enjoy a few days off before heading to London.

Irving wouldn't have it. In the final, crucial moments of a low-scoring slop-fest, Irving drove the lane and spun one of his high-arcing one-handers off the glass. It caromed off, momentarily landing in the hands of the Nets' Spencer Dinwiddie. That is, until Irving ripped it out and found his late-game clutch buddy, Jayson Tatum, open in the corner for a three-pointer that gave the Celtics an 87-83 lead with 45 seconds left.

It was another example of the chemistry and burgeoning trust that has developed between Irving and Tatum, a fellow Duke Blue Devil and the No. 3 pick in the 2017 draft.

"He better make it," Irving said. "Wide-open in the corner, rookie or not, you better make the shot. Step into it and shoot it with confidence, and that's what he's been doing."

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As Boston heads across the pond with a 33-10 record (second only to Golden State's 33-8), the driving force has been Irving, who is relishing his freedom from LeBron's shadow in his first season with the rival Celtics. He was always known for his electrifying handle and sublime offensive gifts. But Irving, suddenly acting like an elder statesman at 25, has exuded not just the ability to drive the ball to the basket, but to drive a first-place team at both ends of the floor.

With the highest usage rating of his career (31.3), Irving has posted his lowest turnover percentage (10.1) and highest win shares per 48 minutes (.218) while also achieving the best defensive rating of his seven-year tenure (104), according to Basketball Reference. Celtics head coach Brad Stevens has witnessed Irving's determination on defense firsthand and doesn't think it's a coincidence.

"I think he's really smart and he knows the narrative, and the great ones can redefine it," Stevens told Bleacher Report. "We always looked at him as a guy who had really good hands, really good feet, was good in isolation and who was a guy that people had maybe underrated on that end a little bit. But I think he continues to get better. Great players want to prove to people all the time that they can do it. He's proven it, and the best way he's proven it is to be consistent with it."

Horford, a four-time All-Star who knows something about leadership, said Irving's style isn't to do a whole lot of talking. That makes what he does have to say that much more impactful.

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"I think in Cleveland, he was one of the younger guys in the group, so as good as he was, he had all the vets in the world that probably gave him all the advice and had everything kind of figured out," Horford told B/R. "He's in a position now where he's one of the veterans, and he can come in and establish himself and command the respect that he brings. He's a champion. ... He's more selective with what he says, but when he says it, it commands that respect and attention, and we listen to him."

Irving's voice was drowned out in Cleveland, where LeBron "sucked all the oxygen out of the room," an Eastern Conference executive told B/R. But the exec doesn't buy that leaving LeBron behind is the only factor in Irving's newfound maturity, and he cautions that Irving and the Celtics are still in the "honeymoon phase."

"By kind of forcing his way out, he's also put an obligation on himself that he kind of has to walk a line, in my opinion," the executive told B/R. "If he goes there and then does not step up to the plate, then it looks more and more like maybe you're the problem.

"If LeBron had never gone to Cleveland, [Irving] wouldn't have been winning," the exec said. "Some of that is a little bit of a natural progression. I don't know that he's all of a sudden become a great leader. But if nothing else, he's the best player on the team and the guy that people look to. Some of that is coming of age."

As big a factor as anything in the Celtics' success to date has been the trust that Irving has demonstrated in Tatum and 2016 No. 3 overall pick Jaylen Brown, the most recent fruits of team president Danny Ainge's robbery of the Nets in the seminal trade that brought an end to Boston's Big Three. The Celtics' youth movement had to accelerate once prized free-agent acquisition Gordon Hayward went down on opening night with a catastrophic ankle injury, and Irving has done his part to nurture it along.

"I think sometimes when young players are able to perform like that, they earn that trust pretty quickly," Stevens told B/R. "To Jayson's credit and to Jaylen's credit, they see a lot of guys that are in their draft class, and those guys just do whatever task is asked. It's also not easy, but it's a form of leadership because it's a willingness to do your role well. I think Kyrie's support of them helps that."

Tatum's clutch corner three-pointer on Saturday night wasn't an aberration; he's averaging 4.3 fourth-quarter points, second on the Celtics only to Irving's 6.3. Irving's relationship with Tatum predates their status as teammates, which has helped embolden their mutual trust. For that reason, Irving has been able to encourage Tatum to embrace the moment without coming across as overbearing.

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"It's happened numerous times where we've had those in-game talks," Tatum told B/R.

"It was already developing into a brother-brother relationship, and then I ended up getting traded here," Irving said. "And from that point, it just continued to develop. I give him his space, and he gives me mine. But whenever he needs an ear to lend or that extra push, I'm there. I told him from Day 1, 'No matter what's going on out here, you can always look to me to exude that confidence in you.'"

Listening to Irving in the visiting locker room at Barclays on Saturday night was like hearing a new man who didn't exist before. Irving never had this kind of latitude or responsibility under LeBron's wing, never had every camera and recording device assembled around him to the exclusion of everyone else in the room. Perhaps that's part of the reason Irving wanted to leave in the first place—to prove that his voice and talent could carry a team.

"When LeBron first got there, Kyrie wasn't ready to lead anyone anywhere," the executive told B/R. "He was still in his early 20s, and I wouldn't have followed him across the street, to be honest with you, in terms of the leadership part. The talent was obviously there, but there wasn't a whole lot else about his makeup or character that engendered leadership. That's not as much a knock on his character as it is, 'Hey, that's a young guy.' ... I would argue that just as much of it has to do with coming into his own as a human, maturity-wise, as it is stepping out of LeBron's shadow."

But out of LeBron's shadow he is. Now, the challenge for Irving is to sustain what we've seen at the halfway point of what has been a surprisingly successful opening act in Boston.

"I think he said, 'Hey, if I'm going to be recognized as a truly great player, I'm going to have to play both ends of the floor and lead,'" the exec said. "Because he definitely didn't do those things in Cleveland."

Partly because he didn't have to. Partly because he wasn't ready. And partly because that was someone else's domain.

Ken Berger covers the NBA for Bleacher Report. Follow him on Twitter: @KBergNBA.