Jaylen Brown Trade Strikes Celtics Twice After LeBron James Signs With 76ers

Before news broke that LeBron James signed with the Philadelphia 76ers, the Boston Celtics’ offseason looked increasingly promising.

Celtics president of basketball operations Brad Stevens emphasized long-term roster flexibility as the reason for trading Jaylen Brown. Although Boston’s return for Brown underwhelmed, the team locked Jayson Tatum’s supporting cast for the next few seasons. Stevens established a multi-year window of optionality, internal development, and financial sustainability around Jayson Tatum.

However, after James signed with Philadelphia, the Celtics are partially responsible for the most talented 76ers roster in decades.

The Celtics-76ers Rivalry Has Suddenly Changed

The Celtics and 76ers have played 23 playoff series against one another — making it the most common matchup in NBA history.

Their postseason history predates the franchise’s existence as the 76ers. Boston defeated them as the Syracuse Nationals in 1953. The rivalry has largely belonged to the Celtics. Boston leads the all-time series 15-8. Before this past year, they had won each of the last six series dating back to 1982.

Tatum and Brown earned their postseason stripes by beating up on Joel Embiid’s 76ers. They eliminated Philadelphia in 2018, 2020, and 2023.

Boston’s dominance over Philadelphia cuts deeper with the NBA Draft. The 76ers picked first overall in both the 2016 and 2017 drafts — passing up on The Jays in back-to-back years.

The rivalry was one-sided for almost 50 years, but the tides have now drastically turned in just three months. Philadelphia won a playoff series in historic fashion over the Celtics, and followed it up with an offseason that landed them Tatum’s co-star and arguably the greatest player in NBA history.

The Celtics Had to Put Themselves First

Trading Jaylen Brown set the 76ers up for this opportunity where “The Process” assembled four solidified stars in Philadelphia. In Boston, it was a painful first step in what Stevens hopes will improve the Celtics’ multi-year championship window.

“Ultimately, when you do a deal, you have to be thinking about you first and the optionality it creates for you,” Stevens said after the trade became official. “If that exact deal came from a team out west and you were comparing the two, then you’d probably take the team out west. But that’s not the way it was working.”

The moves Stevens made alongside the Brown trade give them a promising outlook at that roster flexibility.

Boston shored up its center rotation by locking down Neemias Queta on a contract extension and signing Mitchell Robinson in free agency. They should theoretically make up one-fifth of the Celtics’ rotation while costing less than 17 percent of Boston’s salary cap for each of the next three seasons.

Stevens signed breakout wings Jordan Walsh and Ron Harper Jr. to team-friendly extensions as well. Each of them will cost Boston under three percent of the salary cap. With both players no longer having to worry about their next contract, the Celtics secured their commitment. They still need to prove themselves as reliable playoff-rotation players, but they’re on low-risk contracts and developing in the same program that helped them flash last season.

The decision to pick up Queta and Walsh’s sub-$3 million team options for 2026-27 is helping Boston stay under the luxury tax. In turn, they can shed the repeater tax and have a clean salary cap sheet, creating financial freedom to spend in the upcoming prime years of Tatum’s career.

2026 first-round pick Chris Cenac Jr. was ranked as a five-star prospect out of high school just one year ago. With athletic tools and a strong reputation regarding his work ethic, Cenac could work his way into a rotation spot while playing with a low salary-cap hit in the near future.

Stevens accomplished what he set out to do. That said, the unintended consequences could prove costly as the 76ers formed a superteam in the process.

The Difference In Celtics’ and 76ers’ Championship Approach

Juxtaposing Boston and Philadelphia’s offensive hierarchies will be a fascinating experiment moving forward. The Celtics have committed to a new identity under Tatum as their undisputed engine. His supporting cast thrives in complementary roles, but will be asked to do more. Players such as Paul George, Payton Pritchard, and Derrick White will play prominent roles, but the offense will run through Tatum.

The Celtics can establish their Tatum-centric offense for years to come, especially with most of their roster under contract. Player personnel will change over time, but Boston can begin building continuity in their new identity.

Meanwhile, Philadelphia has an embarrassment of riches for on-ball creators. Head coach Nick Nurse will have to sort out and establish a new pecking order. Their fit together may not be seamless. With so many brilliant offensive players, they can likely work through it, but even then, there are several other questions about Philadelphia’s defense, durability, and depth.

The 76ers are serious championship contenders, and the Celtics are somewhat to blame in that. Still, Philadelphia’s roster is not perfect and, as constructed, only has a one- or two-year window.

Boston flirted with an all-in push during the Giannis Antetokounmpo sweepstakes, but chose to look at the bigger picture. The next half-decade of Celtics basketball may teach a crucial lesson in roster building, one way or another.

Celtics May Be Down, But Certainly Not Out