 In 2005 William returned to Ipatinga, and subsequently became an undisputed starter for the side.On 1 April 2006, William was presented at Grêmio.In 2007, after the arrival of Mano Menezes to Corinthians and the demand of time for players to form their defensive sector, William, who had worked and had credibility with Mano Menezes ended up being requested by the coach and hired by Corinthians.