Willian was expected to return for pre-season training with Chelsea on Friday but the Brazilian has failed to return.
According to Daily Mail, Willian has contacted Chelsea to blame his late arrival on a problem with his passport.
Willian, who has been enjoying an extended break after playing at the World Cup, has been targeted by Barcelona this summer with Chelsea turning down a bid for the Brazilian.
It’s also been reported Real Madrid have submitted an offer for the Brazilian with Chelsea reportedly considering the offer.
Willian is now expected to miss Wednesday’s International Champions Cup match against London rivals Arsenal.