Chelsea winger Willian has instructed his lawyers to take legal action over a "forged" letter purporting to authorise a change of agent.
The Brazil international shared the document on Instagram on Thursday with a statement denouncing its authenticity.
The letter, which Willian says has been "circulated through the football market", claims to sanction a change in his representation until August 15.
It comes with the 29-year-old at the centre of intense transfer speculation linking him to Real Madrid and Manchester United.
"I would like to clarify that I never signed such letter, the content of which I completely deny," Willian wrote on Instagram.
"Finally, since there seems to be clear evidence that my signature has been forged, or anyway misused, I hereby inform that my lawyers are already instructed to proceed with all appropriate legal measures before any competent courts or authorities.
"I hope I have clarified the matter and any possible misunderstanding."
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