Milan confirmed Kevin Prince Boateng will train with the squad until December 31.
The Ghana international is currently out of favour with Schalke 04, but struggling to find a new club.
There had been reports over the summer that he would return to the Rossoneri, always denied by Milan.
Now he is training with the first team, but it remains to be seen whether they’ll offer Boateng a contract in January.
The 28-year-old midfielder left Milan for Schalke 04 in August 2013.