He started at the Nova Safra football school in Rio de Janeiro. His talent was discovered when he was 11 years old and he went to Europe and played in Feyenoord Rotterdams youth squads at Varkenoord He made his debut on August 19, 2000 in a 2–0 victory over AZ Almaar at the age of 17. This was a problem for Feyenoord and Leonardo because a non EU player is not allowed to play under 18 years. So he had to wait until he was 18. He scored his first goal for the first team versus SC Heerenveen. In his first two seasons at Feyenoord he played 44 matches and scored four goals, but mainly he gave assists for his team mates to score. He was part of the Feyenoord team that won the 2001–02 UEFA Cup.