The Brazil international move to the west London side during Mourinho’s second spell in charge of Chelsea FC back in the 2013 summer transfer window.
Willian has won two Premier League titles and the League Cup during his spell at the Blues but the South American has been in and out of the Chelsea FC team under Antonio Conte.
The 29-year-old attacking midfielder has scored six times and has made seven assists in 35 appearances in the Premier League this season.
Manchester United have been regularly linked with a move to sign Willian since Mourinho took over the reins at Old Trafford back in May 2016.
And the Red Devils boss has fuelled speculation that Manchester United could make an audacious bid for the Brazil international.
“I like very much the basic structure of Brasil, its tactical and mentality,” Mourinho told ESPN Brasil.
“There is a mixture between Brazilian natural talent, with a serious approach, physical, tactical.
“It is a team capable of defending well, allowing few goals, with a good support base.
“And then up front with Willian, Neymar, Coutinho and Jesus … All players with outstanding qualities.”
Manchester United signed Serbia international Nemanja Matic in a £40m deal from Chelsea FC in the 2017 summer transfer window.
The Red Devils can finish the season with their third trophy since Mourinho took charge if Manchester United beat Chelsea FC in the FA Cup final at Wembley later this month.
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