NBA Commissioner Adam Silver responded to Morant's actions. Morant later released a statement expressing his regret.
Williams is set to appear in court on April 20.
Game 1 takes place this Sunday at the FedExForum at 2 P.M. CT.
Simmons is now the program's 13th head coach.
The Tigers start off conference play with a record of 1-2.
Memphis is currently searching for a new head coach to replace Merriweather.
Memphis finishes the season with a 26-9 record, the program's highest win total since the 2012-13 season.
Memphis will take on Florida Atlantic in the first round on Friday.
