BOSTON - Someone might want to change their All-Rookie team ballot after this one.
Jayson Tatum, so young that he actually drinks the Gatorade that's on the table when he has a podium game rather than leaving it there for cameras and branding, got 99 out of a 100 possible first-place votes from media folks for the newbie honors announced Tuesday. That left him a vote shy of both Philadelphia's Ben Simmons and Utah's Donovan Mitchell, the dueling favorites for the NBA's Rookie of the Year Award when it's announced next month.
If Tatum merely is the Celtics' favorite rookie, though, that's plenty. And wherever Simmons and Mitchell are at the moment, their seasons and postseasons are over. The Boston kid still is playing.
Tatum scored 24 points, grabbed seven rebounds, dished four assists, pilfered four steals and blocked two shots to lead the Celtics to their 96-83 Game 5 victory over the Cavaliers Wednesday night at TD Garden. His plus/minus rating of plus-19 was second only to veteran Al Horford's (plus-22) and in a pivotal game in which his teammates shot a combined 34 percent, Tatum - who turned 20 on March 3 - hit three of his seven 3-pointers, all but one of his eight free throws and seven of his 15 field-goal attempts overall.
"I think his composure [is impressive], he plays above his age," LeBron James said earlier in the day. "I think the unfortunate events of the injuries that they've had have allowed him to, I believe, get better faster than I believe they expected here. It's given him an opportunity to make ... make mistakes and learn from them and still be on the floor."
Losing Gordon Hayward to a gruesome leg injury in the season's opening game and having Kyrie Irving limp into knee surgery in the sunset of this season did bump most of Boston's players, the rookie included, up a couple spots in coach Brad Stevens' pecking order.
The No. 3 pick in last June's NBA Draft, Tatum was going to get his share of playing time. But he wound up becoming the fifth rookie in NBA history, and the first since Stephen Curry in 2009-10, to score at least 1,000 points and hit at least 40 percent of his 3-pointers. Only eight previous rookies in Boston's storied franchise history totaled 1,000 or more points.
Jaylen Brown, Boston's second-year wing, developed in tandem with Tatum. The pair of lithe, skilled players dripping with potential has most of the league's personnel execs and coaches drooling. Except, with Game 6 on Friday night in Cleveland for the first of two shots at eliminating the Cavaliers, the Celtics are playing as if their future is now.
A truism in the NBA is that, by the end of a rookie's first arduous season, he's not a rookie anymore. Mix in some force-feeding due to Boston's two injured stars and now three playoff rounds, and Tatum is racing to the right on his learning curve.
"I think that we misuse the word 'development' sometimes," Stevens said. "I think we're in the business of 'enhancement.' I think Jayson was ready to deal with everything that comes with this because of who he is and his family and all his coaches before, because he's a very emotionally steady, smart player that was going to perform at a high level above his age.
"I don't know that anybody could guess this as a rookie, but you knew he was going to be really good."
Tatum sorta had to be in Game 5. Brown got matched up in a lot of Boston's defensive coverage of James and picked up his second and third personal fouls in the second quarter. Point guard Terry Rozier looked like his road alter ego, missing six of seven shots in the game's first 24 minutes.
But Tatum - who averaged 12.7 points against Cleveland in three regular-season meetings but is at 17.2 so far in the East finals - had 12 points by halftime, helping the Celtics to their 53-42 lead.
"I just enjoy playing in the big moments, in the big games," Tatum said. "I think that's when I have the most fun, when things are on the line."
It was Tatum racing downcourt to chase down Kevin Love's errant pass into the backcourt and finish with a layup that had Boston up 74-58. And it was Tatum who drew a foul on Kyle Korver with 3:11 left, prompting Cavs coach Tyronn Lue to pull a weary James.
"I thought he was aggressive. I thought he was poised," Lue said of Tatum. "Even though he was scoring the basketball, he didn't try to rush or he didn't press. ... He played like a veteran."
Tatum put in his work defensively Tuesday, but also got as good as he gave. It's become a familiar tactic for defenders to get physically aggressive with him, trying to exploit what at this stage still is limited strength by NBA standards. His father Justin, a basketball coach in St. Louis, has said he plays tall and hasn't yet learned to utilize his base.
"JR [Smith], Jeff Green, they're playing really hard on Tatum and making it very tough," Stevens said. "He's had a lot of experiences over the last couple weeks dealing with playoff defense. I thought Milwaukee guarded him exceptionally hard and were really committed when he drove to the rim to having multiple bodies there. I thought that Philly obviously guarded him very hard. It's hard to make plays at this level in these games, and he's done that pretty consistently."
The numbers back that up. Tatum by halftime had become only the sixth rookie in league history to reach 300 points in the postseason, the first since Jack Sikma in 1978. It was his ninth playoff game of 20 points or more, tying him with Mitchell this season and David Robinson in 1990 for second most by a rookie since 1964; Kareem Abdul-Jabbar had 10 in 1970.
Tatum, Brown and a few other young Celtics have given credit for the team's unexpected success - considering the injuries, anyway - to Al Horford, the most obvious grown-up in Boston's locker room. When Horford was asked late Tuesday what it's like for him being around "these kids," he sounded a little like James three years ago.
That's when Irving was hobbling, eventually blowing out a knee that spring, and Kevin Love was done for the playoffs due to a shoulder injury suffered in the first round. That's also when James looked at the raw help he had from guys such as Tristan Thompson and Matthew Dellavedova, and locked in on the possibility of reaching the Finals.
"It's a lot of fun, just because these guys, they want to play the right way," Horford said. "They play hard. I feel like we hold each other accountable out there. I think that's a big thing. And when those things happen, it becomes fun. It's fun to me. And there's no coincidence why we're in this position right now."
Youth is being served, at least on the Celtics' floor.
Steve Aschburner has written about the NBA since 1980. You can e-mail him here, find his archive here and follow him on Twitter.
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