BILD this morning reports Chelsea could make a bid for the Germany international week.
FCK are reluctant to lose Hector, but have set an asking price of €30 million to sell in January.
Hector, who resisted interest from Barcelona last summer, penned a deal to 2021 this season - with a buyout clause being removed.
"I will not have sleepless nights and I am relaxed," said FCK coach Peter Stoger when asked about the Chelsea rumours.
'If something really happens, we'll deal with it."