BOSTON — First came the scream.
Then the flex.
Then an emphatic chest bump that threatened to knock over teammate Kemba Walker.
Jayson Tatum had just capped his 39-point outburst with an isolation drive that put Landry Shamet on skates before muscling home a tough finish over Montrezl Harrell. Tatum exulted throughout his journey back to the bench, angrily slapping any congratulatory hand a teammate or coach brazenly extended towards him.
"I did get a little excited. I try to be as humble as I can and try to keep a poker face and just move onto the next play. But basketball is a game of emotions and the crowd was into it,” Tatum, back at his more natural whisper, said after Boston’s double-overtime win Thursday.
"I got excited a little bit. But I try to stay calm.”
It’s Celtics fans that are really struggling to contain their excitement. The 21-year-old Tatum is blossoming into a star in front of everyone’s eyes this season and it wasn’t hyperbole when fans chanted MVP during one of Tatum’s late-game trips to the free-throw line.
Tatum is Boston’s best player. It happened way quicker than any of us saw coming. He’s a legitimate two-way threat who gleefully accepts the challenge of going head-to-head with Kawhi Leonard.
But don’t take our word for it; listen to Walker.
"He was incredible,” said Walker. "He made every right play. He made every big shot. He was the best player on the court tonight.”
Tatum and Walker were scheduled to fly to Chicago after the game and will dive headlong into All-Star festivities on Friday morning. There was a time, just a few weeks ago, where it seemed fair to argue whether Tatum deserved Boston’s second All-Star slot over teammate Jaylen Brown.
There’s no discussion now. Ever since getting that All-Star nod, Tatum has taken his game to a different level. He plays with a newfound swagger and a killer instinct he so clearly lacked before.
The 21-year-old Tatum is playing like someone who doesn’t know he’s 21, but someone who knows how damn good he is. He had one second-half stretch Thursday where he produced a poster jam then came back down the court the next possession and hit a side-step 3. It was the sort of stretch that stars have.
All-Star weekend could have been Tatum’s coming out party. But he beat the rush. The best part of it all, Walker — the guy the Celtics acquired to be their best player — seems perfectly content to watch Tatum become the face of the franchise.
"It’s fun. I’m glad I get to be a part of it,” said Walker. "It’s just special. He’s been playing really well but, not only has he been scoring, he’s just been making the right play. I think that’s what’s most important. You’re driving and kicking, he’s seeing his reads, and he’s doing the right things.”
Late in the second overtime, Tatum nearly fumbled the ball on a drive. He managed to collect it then flung it back out to the top of the arc, where Gordon Hayward shuffled over and hit a game-clinching 3-pointer. It was Tatum’s only assist of the night but, man, was it timely.
Most impressive, though, was the way Tatum sought to defend Leonard, especially in the second half after Paul George had been ruled out with a hamstring issue.
“He wants the challenge,” said Celtics coach Brad Stevens. "No one respects Kawhi more than Jayson and appreciates him more than Jayson. He’s going to play his heart out against him on both ends of the court because he knows, if you don’t, you get embarrassed pretty easily. I thought he did a really good job.
"You just try to make those shots as tough as possible. When Jayson is able to [contest] shots, his length is a factor. He did that on a lot of occasions and Kawhi still hit a few, as did the other guys. He played a good two-way game, but he’s been a good two-way player.”
For his part, Tatum shrugged off his defensive efforts.
"It’s definitely a challenge. (Leonard is) a guy I watch film on a lot,” said Tatum. "I have been watching film on since I was in high school. Obviously, one of the best players in the league. Top 2, 2-3 players in the league. You want those moments, just to compete against a guy like that, who’s accomplished so much in this league.”
Tatum’s two-way abilities, and the confidence with which he’s playing at both ends, changes the potential for these Celtics. The team’s ability to truly compete in the East always hinged a bit on what Tatum (and Brown, too) might become. But the ahead-of-schedule blossoming makes Boston an even more dangerous threat.
This always seemed possible. Just not this quick. But Tatum saw where he was headed.
"He’s doing a great job but you can definitely tell that he’s matured, he’s put in that work, and it’s all showing,” said Marcus Smart. "Not just for him but for this team, it’s amazing.”