The Brazil international is facing an uncertain future at the west London side after falling out of favour under Antonio Conte.
Willian was a late substitute in Chelsea FC’s 1-0 win over Manchester United in the FA Cup final at Wembley last season.
The South American took to Instagram to have a subtle dig at his Italian head coach following their cup triumph.
Manchester United are rumoured to be interested in a potential swoop to sign Willian from the 2017 Premier League champions.
FC Barcelona have also been linked with a bid to sign Willian after Lionel Messi and Luis Suarez asked the La Liga title holders to improve their right wing.
Sunday Times reporter Castles is claiming that the Blues would see a potential sale to FC Barcelona more preferable than allowing Willian to move to Manchester United.
“Chelsea’s perspective a sale outside of the Premier League would be preferable especially seeing how Matic did at Man United last season,” Castles told the Transfer Window podcast.
Willian has won two Premier League titles, the FA Cup and the League Cup since his move to Chelsea FC from Anzhi Makhachkala in 2013.
The Blues sold Nemanja Matic to Manchester United in a widely criticised deal in the 2017 summer transfer window.
Chelsea FC haven’t signed any players in the summer transfer window so far.
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