Tillman will start at power forward in Monday's game against the Grizzlies, Brian Robb of MassLive.com reports.
Tillman hasn't appeared in a game since March 6, with four of his absences being the result of a left knee joint sprain. He was cleared to return to action for Saturday's 121-111 win over the Spurs, but he went unused off the bench in a coach's decision. Though he's been outside of the rotation for much of the season, Tillman will get a chance to make his second start of the season as he returns to Memphis, where he spent the first four and a half years of his career before being traded to Boston last February. Jaylen Brown (knee) will sit out Monday, but if he's back for the Celtics' next game Wednesday versus the Heat, Tillman will likely head back to the bench and see his minutes disappear.