According to Chris Sheridan, it says right in the NBA rule book that any intentional physical contact with a referee will result in an automatic suspension.
Any player or coach guilty of intentional physical contact with an official shall automatically be suspended without pay for one game. A fine and/or longer period of suspension will result if circumstances so dictate.”
It looks the Boston Celtics, already without ailing shooting guard Ray Allen, will be without Rajon Rondo in Game 2 of their Eastern Conference quarterfinal match-up with the Atlanta Hawks.
UPDATE: Rondo has officially been suspended one game by the NBA.