The Red Devils have been linked with a sensational swoop to sign the Brazil international from their bitter Premier League rivals Chelsea FC in the summer transfer window.
Willian is thought to be keen on a move away from Stamford Bridge if Chelsea FC boss Antonio Conte remains in charge of the west London outfit.
Manchester United are thought to be weighing up a swoop to sign the South American, although it remains to be seen whether the Blues would sell Willian to a direct title rival.
Chelsea FC were heavily criticised for their decision to sell Serbia international Nemanja Matic in a £40m deal to Manchester United in the 2017 summer transfer window.
FC Barcelona are rumoured to be leading the race to sign the experienced winger in the summer transfer window ahead of interest from Manchester United.
Sunday Times reporter Castles believes Manchester United could make a fresh approach to sign Willian this summer.
“There is a potential for Man United to come back in,” Castles told the Transfer Window podcast. “The price is high. They are looking at other targets.”
Chelsea FC haven’t won the Champions League title since 2012 when the Blues beat Bayern Munich on penalties at the Allianz Arena.
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