What happened: Jaylen Brown joins Kevin Durant and JaMychal Green as the only competitors in NBA history to join an opponent the season after blowing a 3-1 postseason series advantage against them. The unique distinction follows an offseason blockbuster trade that sent the standout wing to Philadelphia. Durant established the precedent by signing a two-year, $54.3 million contract with Golden State in 2016 following his own Game 7 defeat.

Why it matters: Boston's historic collapse against the 76ers occurred during the 2026 Eastern Conference First Round. Moving the All-Star provides the Celtics' front office with financial flexibility under the latest salary cap rules. The blockbuster deal was finalized after an unsuccessful attempt to acquire Giannis Antetokounmpo.

What to watch: Philadelphia will integrate their new acquisition into a lineup aiming to build on their historic comeback during the upcoming 2026-27 campaign.