However, Roberto Calenda has revealed that only a "financial crisis" prevented the 20-year-old from becoming an Inter player.
"At the end of the day [Lucas] had chosen Inter. It wasn't just a verbal agreement, as he had authorisation from Sao Paolo," said Calenda. "There were other interested parties, above all Real Madrid, but less so Manchester United, as [Lucas] never wanted to go there.
"Sao Paolo confirmed they were willing to sell [Lucas]. Inter had the opportunity but chose not to because of the financial crisis.
"Inter began courting [Lucas] a year and a half ago. Family visited Milan and saw Champions League game at San Siro when Claudio Ranieri was coach."
Lucas has made 17 appearances for the Brazilian national team.