Williams (knee) has been ruled out for Sunday's game against the Hawks.
Williams is still ramping up after undergoing right knee surgery in September, and there is no set timetable for his return. The 29-year-old is expected to serve as a backup frontcourt piece, though he will have to compete for playing time with Ousmane Dieng and Aaron Wiggins off the bench. Williams' next chance to play will be Wednesday versus the Spurs.