Willian is keen to remain at Chelsea amid interest from Barcelona, with the Brazilian's representatives currently in talks with the London club over a contract extension.
In January, the 31-year-old will be free to discuss terms with other clubs over a prospective move as his current £120,000-a-week contract is set to expire in June 2020. Barca are closely monitoring the situation.
The length of contract offered to Willian could be pivotal to the ongoing talks at Stamford Bridge, with the Blues historically only offering players over the age of 30 rolling one-year extensions.