Celtics star Jayson Tatum says his mom only allows him to spend endorsement money, not his NBA earnings

• Celtics forward Jayson Tatum only spends his endorsement money and not his NBA salary, a deal he made with his mom.
• Tatum is in the midst of a five-year, $163 million extension with the Celtics.

Boston Celtics star forward Jayson Tatum lives a semi-frugal life, thanks to his mother, Brandy Cole.

Speaking on "In Depth" with journalist Graham Bessinger, Tatum said his mom is his manager and helps handle his finances. One of her rules is that Tatum can only spend his endorsement money and not his NBA earnings.

"We had a deal before I got drafted that I couldn't spend the money I make from the Celtics, that I have to live off my endorsements," Tatum told Bessinger. "Her and my accountant agreed.

"They didn't know that I'd make as much as I did off the court. So in my mind, I gotta spend that money," Tatum said with a laugh.

Tatum has endorsements with Jordan Brand, Subway, and Gatorade, among others. He told Bessinger that his first Jordan signature shoe would be debuting in March.

Meanwhile, Tatum is banking a good amount of money from the Celtics. According to Spotrac, after this season, Tatum will have already made $88 million in the NBA. He's only in the second year of a five-year, $163 million extension.

Tatum told Bessinger that his mom's access to his finances can occasionally be awkward, like when he goes on vacation with friends and spends $12,000 in one night. He said he once woke up to a call from his mom asking where that money went.

Cole also told Bessinger that Tatum occasionally splurges.

"Jayson likes nice things," Cole said. "He likes nice watches. Technically, I can't say no, right?"

Former NFL tight end Rob Gronkowski followed the same plan as Tatum, spending only his endorsements money and not his NFL earnings. He told Business Insider in 2018 that he told players to live "simple" and save their extra money.

Though Tatum does like to spend his money, he also told Bessinger that his spending is in "moderation." He told Bessinger that there was a time when he would have to check with his mom to see if he could buy gas for his car.

"I think we just have a different level of appreciation," Cole said.