The disbelief started to set in with the crowd, but it was obvious Jayson Tatum was having one of those nights. The Celtics star was the clear best player in their blowout win over the Bulls on Saturday as Tatum gave the United Center crowd a memorable performance.

Tatum finished with 43 points, 15 rebounds and 10 assists in his third-career triple-double Saturday. It wasn’t just that: He shot 16-for-24 from the field and 9-for-15 on 3-pointers. It’s those 3s that puts Tatum in rarified air as he flirted with NBA history. He’s also the first Celtics player ever to hit those marks as part of a triple-double performance.

Tatum became just the second player ever to put up a triple-double with at least 40 points, 15 rebounds, 10 assists and nine made 3-pointers, per NBC Sports Boston’s stat guru Dick Lipe. Only James Harden has hit those marks over the league’s long history. Harden put up 53 points, 16 rebounds and 17 assists, shooting 9-for-16 on 3s, in a Dec. 31, 2016, win over the Knicks during his prime.

“Some nights, you just feel really good,” Tatum told NBC Sports Boston. “Shots going in. The ball is hot. You’re in the right spots. The big guys, they did a great job of screening. We got guys who space the ball, so if you help too much, I kick it out. If you don’t, then I get to do my thing.”

The Celtics needed Tatum at their best, too, as the Bulls hung around through the first half of Saturday’s game. Tatum was masterful in the third quarter, finishing with 18 points and shooting 4-for-5 on his 3-pointers. That was all the C’s needed as they didn’t sweat much come the fourth quarter.

Saturday’s win was also another look at Tatum’s improved all-around game. He finished with double-digit rebounds for his sixth straight game. He’s also averaging a career-high 9.0 rebounds and 5.5 assists per game. Plus, when Tatum is at his best, fans come to see the perennial first-team All-NBA talent as he gave the Chicago crowd a show.

“I’ve played a lot of games in my life,” Tatum said. “It’s a feel thing. You find moments where defense opens up and you attack and read what they’re doing. If they’re blitzing the ball screen three times in a row, you gotta make the right read. So, it opens up.”

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