Maurizio Sarri is certain Willian will remain at Chelsea this summer after holding positive talks with the player this week.
The Brazilian forward has been linked with a big-money move to Manchester United, Barcelona and Real Madrid, but Sarri insists there is no chance of him leaving.
'Willian? I spoke yesterday with him about his late arrival, not about his future. It was a very positive conversation,' Sarri told reporters.
'I am happy about it. I think there is not a Willian problem. I think he will stay. I am very confident.'
The Chelsea boss admitted he found it strange and frustrating that Willian failed to report for pre-season training on time earlier this week.
Willian was unable to get to Cobham following his post-World Cup holidays because the Brazilian's passport had expired, but the pair appear to have buried the hatched after a one-on-one conversation this week.
Sarri however could not provide any assurances over Thibaut Courtois - also a Real Madrid target - and remained particularly coy when quizzed about the goalkeeper's future.
'I don't know at the moment,' Sarri added. 'For now Courtois is the goalkeeper of the club.
'I don't know in the future, it depends on the club, and especially on him I think, but I hope Courtois will be our goalkeeper.'