The German international appears convinced the striker is heading to the Bernabeu with comments that also suggest Lassana Diarra may be on his way out of the Spanish capital
Aguero looks set to depart Atletico this summer, with several of Europe's big clubs interested in the striker.
Madrid appear to be in the driving seat for the player, after Aguero declared he would prefer to stay in Spain. Atletico's arch-rivals would be in a position to meet the €45 million (£39.7m) buy-out clause necessary to prise 'El Kun' away from their city rivals.
Ozil, who enjoyed an impressive debut season at the Bernabeu, has declared that the club will give the No.10 shirt to Aguero if he signs this summer.
"Madrid have reserved the number 10 shirt for Aguero," the German international told Saz Aktuell.
The Real Madrid man's comments have cast further doubt over Lassana Diarra's future in the Spanish capital, with the former Portsmouth midfielder being linked with a summer move to Manchester United, Liverpool, Tottenham and Juventus.
Aguero enjoyed a prolific season for Atletico, scoring a total of 27 goals in 41 appearances for the La Liga outfit.