The Celtics recalled Williams from the G League's Maine Celtics on Wednesday.
Williams has rejoined Boston ahead of Wednesday's game against the Thunder, but he's unlikely to be featured in the rotation. The rookie second-round pick saw extended run Tuesday in Maine's 130-105 win over the Cleveland Charge, finishing with 13 points (5-9 FG, 1-1 3Pt, 1-4 FT), nine rebounds, four blocks and one assist in 27 minutes.