If Brown makes an All-NBA team, he'll be eligible to sign a four-year supermax extension with the Celtics this summer. That contract would begin at 35 percent of the 2024-25 salary cap and contain 8 percent annual raises. But if he doesn't make an All-NBA team, the Celtics may be far more limited in what they can offer him in an extension.
Under the NBA's current collective bargaining agreement, teams can offer players no more than 120% of their previous salary or 120% of the estimated average salary (whichever is greater) as the starting salary of a new extension. With Brown set to earn $30.7 million in the final year of his contract next season, the Celtics can offer him no more than $36.9 million as the starting salary of an extension if doesn't make an All-NBA team. The four-year total comes out to nearly $165.2 million, which is likely tens of millions less than he could make as a free agent in 2024.
However, the NBA and the National Basketball Players Association are currently negotiating a new collective bargaining agreement that could take effect as early as this summer. One of the proposed changes could make an extension far more realistic for Brown and the Celtics even if he doesn't make an All-NBA team this year.
According to Shams Charania of The Athletic, the NBA and NBPA have discussed allowing teams to instead offer 140 or 150% of a player's previous salary as the starting salary of a new extension rather than 120%. If that change goes into effect this summer, the Celtics should be able to offer Brown a full max or near-max extension, depending on where the salary cap lands in 2024-25.
Since Brown will have eight years of NBA experience when he's eligible for free agency in 2024, he could sign a contract with a starting salary worth up to 30% of the 2024-25 salary cap. While the league hasn't issued an official projection for that year's salary cap, we can use RealGM's projection of $140.7 million to give a ballpark estimate of what Brown could earn as a free agent.
Regardless of whether Brown re-signs with the Celtics or heads elsewhere, his max deal would start at $42.2 million (30% of the $140.7 million cap). He'd be eligible to sign a five-year, $244.8 million max deal with the Celtics (8% annual raises) or a four-year, $181.5 million deal with any other team (5% annual raises). Either way, that's far more money than he can receive from the Celtics under the current extension rules if he misses the All-NBA team this season.
The proposed extension changes would more than bridge that gap, though. Regardless of whether the Celtics could offer him 140% of his 2023-24 salary ($43.0 million) or 150% ($46.1 million), both would exceed his max salary under a $140.7 million cap. So if the new CBA goes into effect this summer with those new extension rules, the Celtics could offer Brown a four-year extension worth a projected $189.1 million.
There are a few caveats here, however.
For one, if the 2024-25 cap comes in significantly higher than $140.7 million, Brown's max salary will rise accordingly. If it lands at $150 million, for example, he'd be eligible to sign a new contract with a starting salary of $45 million as a free agent. If the new CBA limits teams to offering no more than 140% of the player's previous salary as the starting salary of an extension rather than 150%, the Celtics would still come in a few million below what Brown could earn as a free agent.
Brown could also decide to bet on himself rather than lock in an extension. If he makes an All-NBA team next season, he'll be eligible to sign a five-year supermax contract with the Celtics in free agency starting at 35% of the salary cap. If the 2024-25 cap lands at $140.7 million, Brown would be eligible for a five-year, $285.6 million (!) supermax.
There's always a chance that the new CBA will include changes to supermax contracts, too, particularly since they haven't quite panned out as hoped since being implemented in 2017. If the eligibility criteria changes, Brown might be able to sign a supermax without making an All-NBA team in either of the next two years.
There's no guarantee that money alone will be enough to convince Brown to remain in Boston beyond 2024. When Logan Murdock of The Ringer recently asked Brown whether he wanted to stay with the Celtics long term, he demurred.
“I don’t know. As long as I’m needed. It’s not up to me,” he said. “We’ll see how they feel about me over time and I feel about them over time. Hopefully, whatever it is, it makes sense. But I will stay where I’m wanted. I will stay where I’m needed and treated correct.”
A $200-plus million contract could go a long way toward smoothing over any hurt feelings. Whether the Celtics can offer Brown such a deal this summer will come down not only to his All-NBA status, but also what the new CBA has in store.