If an uninitiated observer watched him Saturday, all of the above would be surprising to learn.
Tatum went 3-of-14 in Boston's 109-103 loss to the Miami Heat in Game 3 of the Eastern Conference Finals, and he totaled 10 points, six turnovers and four assists in 41 minutes. Yet that doesn't begin to tell the story.
Tatum's foil on the Heat, Jimmy Butler, missed the entire second half with knee inflammation. The game and momentum in the series could've been seized, but a lack of focus and intensity from Tatum and the Celtics prevented them from matching Miami's effort.
"All they talked about was upping their physicality and being embarrassed at home, and we didn't match that from the start," Boston coach Ime Udoka said after the game. "We got into complaining and let it take us out of our game. It's disappointing to come out that flat in a conference finals game."
It's generous to describe Tatum's first two shots of the game as shots. They were more like flings. When he couldn't get by his initial defender, he just sort of flipped the ball toward the rim and missed. Thanks to the shot clock winding down, he deserves a little leeway on the first one, but those early unanswered prayers set the tone.
It was going to be a tough night for getting to the rim, and that spelled trouble for Boston.
This season, Tatum shot 38.4 percent on shots in the 3-15 foot range, good for 183rd among the 215 players with at least 100 attempts (and last among the 23 with at least as many attempts as Tatum). He was 0-of-5 on those attempts Saturday.
He was settling. And whether it's that or bouts of streakiness with his jumper, Tatum is still prone to letdowns that can upend the Celtics.
Saturday marked the fifth time this postseason that Tatum took at least 10 shots and finished with a 45-or-under effective field-goal percentage (league average in 2021-22 was 53.2). Boston is now 1-4 in those games. Dillon Brooks, Jalen Brunson and Jrue Holiday are the only players with more such performances in the 2022 playoffs.
Tatum is barely 24 years old. He figures to be a perennial All-NBA selection and occasional MVP candidate for the foreseeable future. Everyone has bad games, but Tatum's rough outings need to be spread out a bit more—especially on the game's biggest stage—for him to crack the NBA's top tier.
And he seems to know that.
"Unacceptable," Tatum said of his Game 3 performance. "I gotta play better. I left the guys hanging tonight."
Losing at home isn't ideal, but Boston already stealing one on the road keeps this from feeling catastrophic. The Celtics have lost five games in the postseason. They followed up each of the previous four with wins, and their average margin of victory in those games was 17.3.
If they bounce back in similar fashion in Game 4, the memory of Saturday's dud will quickly fade. And the off shooting nights notwithstanding, Tatum has still developed into one of the game's more trustworthy stars (even if he isn't in that aforementioned top tier).
Just like his team has rebounded from losses in the playoffs, Tatum is averaging 36.0 points, 7.5 rebounds, 5.8 assists, 4.8 threes and 2.3 steals while shooting 48.6 percent from the field and 39.6 percent from three in his individual postseason bounce-backs (games immediately following those with the sub-45 effective field-goal percentage).
"I have the utmost confidence in my guys," veteran Al Horford said after Saturday's loss. "Time and time again, [Jaylen Brown] figures it out, Jayson figures it out. Those guys are battle-tested."
The big man is right. Brown and Tatum are eighth and 10th, respectively, in conference finals minutes played before turning 26 (Tatum is third when you drop the age qualifier to 25). Since January 1 (including the postseason), Boston is an NBA-best plus-11.1 points per 100 possessions (thanks to a 117.9 offensive rating and a 106.8 mark on the other end).
They're banged up, but the Celtics still seem to have the highest ceiling of any team standing (save perhaps the Golden State Warriors).
If Marcus Smart (nursing an ankle injury) and Robert Williams III (missed Saturday's contest with a knee injury, but he could be back as early as Game 4) can give Boston 85 percent of their best, the team can be a nightmare.
When you combine decent health up and down the roster with Tatum playing at or near his best, the Celtics look unbeatable. In the regular and postseason, the starting five is a staggeringly good plus-21.6 points per 100 possessions.
Through three games of the Eastern Conference Finals, Miami has made the Celtics look human. But there's more than enough evidence to suggest Tatum and his teammates can make all the talk about his top-five status feel warranted.