Shakhtar Donestsk CEO Sergei Palkin has told Sky Sports News' Bryan Swanson the club have received a bid from Chelsea for Willian.
Over the weekend Blues boss Andre Villas-Boas labelled the Brazilian international an 'interesting' player, although he also hinted he only wanted players that were not cup-tied in other competitions.
Palkin has revealed Chelsea's offer to be €20million (£16.7m), something that was swiftly rejected as the 23-year-old is 'not for sale'.
The bid falls well short of Shakhtar's valuation with the Ukraine giants believed to be holding out for £29million for the former Corinthians man.
"We have received a bid from Chelsea for Willian valued at €20million, but he is not for sale," confirmed Palkin.
The Stamford Bridge side have already been busy during the transfer window, bringing in England international Gary Cahill from Bolton.
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