When a team trades a superstar for a younger player, they usually do so for control as much as upside. Superstars asking for trades are almost always armed with the threat of free agency, whereas young players, for the most part, have less freedom of movement. A first-round pick can't change teams by choice until after his fifth season, but given the financial risks involved in doing so, they more often delay free agency until after their eighth or ninth season through a rookie extension. Sure, having Anthony Davis for one year is nice, but having Brandon Ingram for six is a whole lot nicer. This is the logic that governs most blockbuster trades: immediate talent for long-term security.
What makes a rumored trade between the Brooklyn Nets and Boston Celtics involving Kevin Durant and Jaylen Brown so interesting is that it essentially reverses that dynamic. Durant is 33 years old, yet he comes with four seasons of team control. There is a very realistic chance that he finishes his career with whatever team he plays for next. Brown is eight years younger at 25, but comes with barely any team control. His contract lasts two more seasons, but because of a few quirks in the CBA, he is virtually guaranteed to decline a contract extension and become an unrestricted free agent in 2024.
The NBA caps the majority of contract extensions at a 20 percent raise on the prior season's salary. For most young stars, this isn't a problem. It usually just entails jumping from one max figure up to the next. But Brown isn't like most young stars. He couldn't negotiate a max rookie extension for himself in 2019, and that has enormous ramifications for him now. First and foremost, only max rookie extensions are eligible to last five years. Had Boston paid Brown a bit more, they'd have him under contract for another year, and he'd probably be a bit more valuable as a trade asset.
But more importantly, that sub-max deal will guarantee Brown a $28.5 million in base salary for the 2023-24 season. That means, with a 20 percent raise, he'd be in line to make roughly $34.2 million in the 2024-25 season on an extension. However, as an unrestricted free agent, Brown could make anything up to his max of 30 percent of the salary cap.