When Jayson Tatum got in trouble in elementary school, it was often Kobe Bryant’s fault. Teachers weren’t thrilled when the Celtics breakout star would sit in class and watch YouTube highlights of the Mamba. “The older I got, the more they understood that I was going to be in the NBA,” Tatum tells me, grinning. “I mean, school was very important. But I needed to watch basketball.” This often caused trouble at home, too, when he’d try to re-create his favorite move: Kobe’s impossible-to-stop baseline fadeaway.

“I remember my dad used to hate that I did it,” says Tatum, tucked away under the foliage in the back of L.A.’s Sunset Marquis. “It was such a bad shot for a second grader.”

All the more surreal, then, that he says this in L.A., the day after the Lakers legend generously decided to mentor the young Celtic, a rare one-on-one workout between longtime East-West rivals. And what was Professor Vino’s advice for his new student?

“Shoot every time,” he recalls. “Pass if you have to. But if not, shoot it.”

Suit, $2,500, by Prada / Shirt, $442, by Wacko Maria at Union Los Angeles / Earrings throughout, his own Coat, $1,495, by Boss / Sweatshirt, $595, by Fear of God / Shorts, $450, by Just Don / Sneakers, $110, by Nike / Socks, $8, by American Apparel

If Tatum plays the way he did to cap his first season in the league—putting on one of the greatest rookie campaigns in playoffs history and leading the Celtics to within minutes of an Eastern Conference title—that “me first” (and second, and third) Mamba mentality just might turn him into the NBA’s next great killer. After all, he’s armed with a Kobe-like arsenal of skills: a deadly jumper, balletic footwork, a see-you-later first step. Even on a team with Kyrie Irving, Tatum has emerged as the bedrock of Boston’s future. See: Game 7 of the Eastern Conference finals, where he put LeBron James on a poster.

Not bad for a guy who less than seven years ago was a gangly teenager (in, it’s worth noting, a Kobe Bryant jersey) thirstily tweeting at LeBron James for a follow-back. (James did eventually follow him back.) James also welcomed Tatum to the league by swatting his first-ever NBA shot, a rookie debut during which, Tatum says, he was “extremely nervous” and more than a bit starstruck. “Early in the season, when we played LeBron or the Greek Freak or Golden State, right before tip-off, I would just look at them,” he says. “Like: This is my life. Damn. I’m 19, right next to KD, getting ready to play basketball.”

Now he’s 20—and dunking on them.

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“I think that anytime a guy has a year like that as a rookie, if you say that you expected it, I don’t know that that would be honest,” says Celtics coach Brad Stevens. “He didn’t ride the emotional roller coaster like a lot of young players do. And that kind of goes back to who he is. He’s got a maturity about him that is unlike most people his age.”

Tatum credits that uncommon demeanor to his mom, Brandy, who, when he was just a kid growing up in St. Louis, dragged him along to her classes. (She eventually earned her way to three degrees.) “I knew when I was in the classroom I gotta be quiet,” he remembers. “And if I didn’t, she was gonna take me to the bathroom and whoop me in front of everybody.” Now she lives three floors above Tatum in Boston, in an apartment she shares with his stepdad and where she’s still tasked with feeding the six-foot-eight NBA superstar-to-be.

“I spend most of my time up there in their apartment, ’cause there’s always food up there,” says Tatum. “I don’t have anything to eat in my house but chips and Gatorade. And when I’m gone or away for a long time, she’ll do my laundry or clean up the house. If I come back from a road trip and we get back, like, three in the morning, she’ll cook and leave a plate in my refrigerator.”

Coat, $2,495, and jacket, $298, by Polo Ralph Lauren / Pants, $85, by Nike

If his fridge is not yet MTV Cribs–worthy, maybe it’s because he left behind his teenage years just seven months ago. He still looks young: like a child’s drawing of a human—all spindly arms and legs, no torso—with a thin goatee that doesn’t quite connect to the scraggly whiskers framing the sides of his face. Then there’s a public lifestyle he’s not quite used to, like the time earlier this year when Denzel Washington approached him at a movie premiere. “I still think it’s mind-blowing when famous people know who I am,” says Tatum. But despite that bright-eyed youth at heart, he’s real tired of hearing that he’s good…for a 19-year-old rookie: “I couldn’t wait for this year to be over with so I could get that title”—rookie—“away from my name.”

Even though his mom still makes him late-night tacos, his game is already far beyond rook status. Off-season tape shows a Mamba-worthy fadeaway. And now, despite Dad’s objections, it’s a well-honed weapon that not even a seven-foot paint kaiju like Joel Embiid can stop him from getting off. The talent is there. But while Coach Stevens lauds his forward’s “quiet confidence,” you wonder if that inner calm might need some stoking. Kobe’s confidence, of course, was never quiet. Stevens says he’s only ever seen Tatum’s heart rate elevated when arguing with teammates about his alma mater, Duke, while Bryant once famously berated his teammates for being soft like two-ply toilet paper (Charmin, to be specific). In their one-on-one training session earlier this summer, Kobe outlined his daily mind-set for the young fella: “If you told yourself that your life, your family’s life, your kid’s life depended on it, how would you go about practice? How much does this game mean to you for you to be the best?”

Jacket, $1,790, and polo, $590, by Thom Browne

If you’re looking for traces of that in Tatum, look no further than that Game 7 dunk on LeBron. Not content to merely posterize the best basketball player on the planet, Tatum, as he turned to run back down to the defensive end, ran chest-first into the much bigger James. “I don’t know why I yelled and bumped him,” he says now. “But I’m glad I did. I will always remember that. But I was running back on defense like, ‘Oh, my God.’ I couldn’t believe what I just did.” The next possession down the court, his team trailing by two, the Boston crowd poised to explode into frenzy at the bidding of their young king, Tatum found himself with the ball on the wing. A true Mamba disciple, he shot his shot—a difficult, off-the-dribble three—and drained it. Just like a killer would.

Clay Skipper is a GQ staff writer.

A version of this story originally appeared in the October 2018 issue with the title "The NBA's Next Mamba."

Styling by Kelly McCabe / Grooming by Tasha Reiko Brown

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