Italy international Luca Toni, Breno, Christian Lell, Andreas Goerlitz, Anatoli Timoschtschuk, Jose Sosa and Alexander Baujohann could all leave the club in the January transfer window.
“The squad will surely be smaller after the winter break,” Hoeness told German magazine Sport-Bild.
“People will stay as long as they prove themselves, but I assume there will be some changes.”
