Chelsea head coach Maurizio Sarri admitted he is not happy with Willian and plans to hold talks with the star attacker about his delayed return to Stamford Bridge.
Willian has been linked with Manchester United and Real Madrid, and his Chelsea future was thrown into more doubt when the Brazil international failed to report for pre-season training on time.
An expired passport was reportedly behind Willian's delayed return to London, though Sarri conceded he found the situation "strange".
"I want to speak to him before I answer these questions. I want to speak to him," Sarri told reporters after Chelsea lost to Arsenal 6-5 on penalties following Wednesday's 1-1 draw at the International Champions Cup in Dublin.
"I am not happy about this situation but before I answer, I would like to speak to him."
Willian is not the only Chelsea player to be linked with a move away as doubts remain over team-mates Eden Hazard and Thibaut Courtois.
Hazard and Courtois have both attracted interest from European champions Madrid.
Asked for an update on the trio, Sarri replied: "Not at this moment, no, because I will see them on Saturday for the first time. I don't know the situation in this moment. There is no news.
"We are talking about top players. Every club wants to keep their top players and we are trying to do it."