What happened: Boston sent Jaylen Brown to Philadelphia during a sweeping summer overhaul. Paul George, Mitchell Robinson and Mike Conley joined a veteran-heavy roster built around a developing young core.
Why it matters: Philadelphia paired Brown with LeBron James, while New York enters 2026-27 as the defending champion. Those rival rosters raise the stakes for Boston’s reworked rotation and longer-term plan.
By the numbers: The Celtics won 56 games in the 2025-26 season.
What to watch: Training camp in October will offer the first test of how the veteran additions fit together. Boston’s early rotation should clarify whether the overhaul preserved its place among the East’s contenders.