The 29-year-old has attempted to play down talk of a move away from West London, however, and Luiz is certain that his Brazilian compatriot will not be lured away.
"We never talked about him leaving. We are friends for a long time," he told reporters after Sunday's Community Shield defeat to Manchester City. "Since the beginning, he told me he loved Chelsea.
"To leave Chelsea, would be something totally out of the reality - if he really wanted to leave or if Chelsea really wanted to kick him out. This is not the reality. Chelsea loves Willian, Willian loves Chelsea, so that's great.
"He's a fantastic player and a fantastic friend. I've known Willian since I was eight, so a long time. Willian loves Chelsea. He played after coming back after the World Cup, and he has already shown his quality. I wanted him to stay."
Willian was responsible for 13 Premier League goals last season - six of his own and seven assists - but grew frustrated under former boss Antonio Conte.