Brandy Cole, Tatum's mother, confirmed the news to Adam Himmelsbach of the Boston Globe:
"When he'd talk about [the contract] it was never about the dollar amount. He wanted to be a max player because that signifies your level of talent and the caliber of player you are. I think that was always the priority for him, striving to be one of the best and to leave his mark in this league. So I think that's always his focus. When you work like he does and have the passion for the game he does, the money will come."
Himmelsbach noted Tatum's deal includes $163 million in guaranteed salary, with the contract maxing out around $195 if incentives are met. Tatum also holds a player option for the final season.
ESPN's Adrian Wojnarowski first reported the deal.
Tatum established himself as a go-to superstar for the Celtics in 2019-20. The Duke alum set career highs in scoring (23.4 points per game), rebounds (7.0 per game), assists (3.0 per game) and shot 40.3 percent from three-point range.
The Celtics originally owned the No. 1 pick in the 2017 draft before moving down two spots in a deal with the Philadelphia 76ers to select the St. Louis native.
Even though point guard Markelle Fultz, who wound up being the top pick by Philadelphia, was considered the top prospect in the 2017 draft class, Celtics general manager Danny Ainge was high on Tatum because of his positional versatility.
He told reporters in June 2017:
"I think that we're all seeing the way the game has evolved. And you really can't have too many versatile players that can play multiple defensive positions. I think that we, in Jayson and in Semi [Ojeleye], and Kadeem Allen and Jabari Bird, they all sorta fit that category. The three of them are swing or wing players. Semi can play some of the 4, and Jayson can play some of the 4, we think, in time. So yeah, that's the way the game is headed."
Tatum was an integral part of Boston's rotation during the 2017-18 season. He averaged 13.9 points and 5.0 rebounds per game and led the Celtics in three-point percentage (43.4).
The 2018-19 season saw Tatum increase his scoring average (15.7), but his shooting efficiency got worse. His field-goal percentage went from 47.5 to 45.0, and his three-point percentage fell to 37.3.
Boston's playoff series against the Milwaukee Bucks was particularly frustrating for Tatum. He was held to 36.4 percent shooting overall (12.5 percent from three-point range) in five games.
Despite those struggles, an NBA general manager told Sean Deveney of Sporting News in May 2019 that Tatum is still a player with the potential to be a franchise building block.
"You can build a team around Jayson Tatum," the GM said. "He can be your No. 1 option. I really believe that. He can create for himself. He can get to his spots. He has a beautiful shot. But I don't know if you can win with Jayson Tatum as your No. 1 guy. So if you're rebuilding, you know, you have to think about that."
Some of that assessment has turned out to be right. Tatum still hasn't won a championship, but he's only 22 heading into his fourth NBA season. The strides he made in the second half of last season suggest the Celtics can play for titles with him as their best player.
Boston advanced to the Eastern Conference Finals last season for the third time in four years.
"I think he would love the idea of being able to spend his entire career here if that meant putting banners up," Cole told Himmelsbach. "He wants to not just say that he played here his whole career, but that he brought the city of Boston a couple of banners and his number is retired. I’m certain he would love that."
With a nucleus of Tatum, Jaylen Brown, Kemba Walker and Marcus Smart, the Celtics are poised to be contenders in the Eastern Conference for a long time.