What happened: The Boston Celtics face the Philadelphia 76ers on Tuesday night in a matchup centered on possession control. Boston has emphasized perimeter pressure while integrating center Mitchell Robinson to bolster offensive rebounding.

Why it matters: Controlling possessions looms large after Philadelphia eliminated Boston from postseason contention earlier this year. Ball security and extra chances on the offensive glass will dictate tempo against the division rival.

What to watch: Boston and Philadelphia tip off Tuesday at 8:00 PM ET.