Bayern Munich have slapped a £30million price tag on Chelsea target Mats Hummels, according to reports.
The German defender has lost his place as a regular starter at the Allianz Arena and Maurizio Sarri reportedly wants to improve his backline.
According to The Sun, the Blues must cough up the cash by January 14, with Bayern keen to ensure they have time to replace the centre-back.
Hummels is said to be interested in a potential move to Stamford Bridge after falling out of favour under Bayern boss Niko Kovac.
The 30-year-old won the World Cup with Germany in 2014 and has long been considered one of the best defenders in Europe.
It is understood that while Chelsea are working on a number of January deals, Sarri has made a centre-back his top priority.
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