That important member is assistant coach Dave Joerger who is a guy who serves the role of offensive coordinator for coach Doc Rivers’ staff. This comes after Joerger has been undergoing treatments for his cancer for the past couple of weeks before the road trip is forcing him to stay in Philadelphia.
Per Adrian Wojnarowski of ESPN:
Joerger told the Sixers players, assistant coaches and staff of his cancer in a post-game meeting on Saturday night in Indiana. He had already told a small group of Sixers officials – including coach Doc Rivers, President of Basketball Operations Daryl Morey and owner Josh Harris – of his recent diagnoses.