Jose Mourinho considers David Luiz to be an integral part of his Chelsea's plans - suggesting he will not be allowed to leave.
Sky sources revealed on Wednesday that La Liga giants Barcelona have set their sights on the Brazil international, with a formal offer put on the table.
Mourinho has previously gone on the record as saying that there is 'no chance' of a sale being sanctioned, and he is not about to waver in that stance.
The Portuguese tactician has inherited an abundance of riches upon his return to the managerial hot-seat at Stamford Bridge, but he believes Luiz has a big role to play heading forward - at the heart of the Blues' back four.
Mourinho said in The Sun: "I have known of David Luiz from the very beginning so I know him very, very well.
"And before I came back to Chelsea, I watched him week after week.
"I see him as a centre-back because he has an important quality for a footballer - he can build from the back.
"He is very comfortable and confident with using the ball from the back - he does not play direct.
"And he can improve, especially defensively. He can be much more effective, much more solid. But the potential he has is amazing, incredible."