Williams (knee) has progressed to playing 3-on-3, Brian Robb of The Springfield Republican reports.
Williams remains one to three weeks away from a potential return, so it would certainly be a bonus if he manages to play in the Celtics' Round 1 series against the Nets. Still, it's good to know he's progressing well, and there's a strong chance he'll be back for the second round if Boston can take care of business.