Spurs boss André Villas-Boas is a keen admirer of the playmaker, who he tried to lure to Stamford Bridge last winter while he was still in charge of Chelsea.
The Blues have also been linked with a move for the 24-year-old, who telephoned his manager Mircea Lucescu to inform him that he would not attend the start of a training camp this week.
And Lucescu blasted Willian’s attitude, branding the player “unprofessional” and hitting out at his representatives.
“I think it was unprofessional of him,” said the Shakhtar boss.
“The president decided to do everything possible to sign a player of Willian’s level, who already has experience of playing at a high standard.
“We look forward to having Willian again and I would like him to come back and behave as he did before – as a professional and decent man.
“I would like him to solve his problems in a civilised manner here in Donetsk, and not by phone. I have great respect for Willian and I would not like him to be put under pressure by the people who surround him, and who perhaps advise him the wrong things.
“He should reject the advice of those who surround him – they are not doing very good things.”
The player himself sparked fresh reports linking him with a move to the Premier League when he admitted he would “love” to play in England earlier this month.
He said: “I hope to move there [to the Premier League]. Maybe next season, or even this month, but it’s difficult to say anything because I’m totally focused on my work here, and I prefer not to lose my grip.
“Who knows, maybe I’ll get offers not only from clubs in England but teams from other countries too. Let’s see what happens.”
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