Oliveira made his debut in the second half of the 2006–07 opening-day match against S.S. Lazio, heading past Angelo Peruzzi from the goalline in a 2–1 home win. However, he scored only twice more after that for the "Rossoneri" in the league, adding two more in their run in the Coppa Italia; he spent most of the season under the stress of the October 2006 kidnapping of his sister, Maria Lourdes, who was released unharmed on 12 March 2007.