De Bruyne wanted by Werder Bremen
The Belgian, who enjoyed a hugely successful loan spell at the Bundesliga side last season, has started only two Barclays Premier League matches this term.
He was left out of the squad for Tuesday night's 4-0 Champions League win at Steaua Bucharest, with questions over his omission prompting Blues boss Jose Mourinho to call a halt to his pre-match press conference.
Bremen general manager Thomas Eichin told the Bild newspaper: "Should Kevin be unhappy, we are an eager first contact.
"I am in contact with his agent and am informed about Kevin's situation at Chelsea."
The 22-year-old scored 10 goals in 32 Bundesliga games for Bremen last season.
Eichin added: "I know Kevin, if he doesn't play it is certainly a big problem for him.
"Let's wait and see what happens in the winter. We will be ready, if there is a possibility, to get him."