Benfica coach Jorge Jesus concedes they could lose Nemanja Matic this month.
The Serbia midfielder is a top target for former club Chelsea.
Jesus admitted he had no control over keeping his star player, saying: "The coach is here only to train the players.
"With these issues, I am always the last to know.
"We sell players all the time and in Portugal we have to live with this situation.
"If Matic goes, then I have to find another solution."