On August 2, 2005, Williams and teammate James Posey were two of thirteen players involved in the biggest trade in league history that saw them being dealt to the Miami Heat in exchange for shooting guard Eddie Jones.
O 2 de agosto de 2005, el e o seu compañeiro de equipo James Posey foron dous do trece xogadores envoltos no maior traspaso da historia da liga que lles levou a Miami Heat, a cambio do escolta Eddie Jones.