Milan Badelj has reportedly already asked to leave Lazio in January due to a lack of playing time.
The Croatia international turns 30 next month and joined in August as a free agent after his Fiorentina contract expired.
After 12 competitive appearances this term, many of them off the bench, Il Messaggero newspaper claims Badelj has complained at the situation.
He even put in a transfer request, with Milan interested in picking up the man who already has 44 senior Croatia caps to his name.
Badelj had been very close to Milan over the summer before opting for Lazio.