Willian formed a close relationship with Jose Mourinho in his time at Stamford Bridge, something the 29-year-old has not found with Antonio Conte.
'There were a few conversations with my agent. I worked with Mourinho and I became his friend as well', Willian told Goal.
The Brazilian winger has fallen behind Pedro in the pecking order and was linked with a reunion with his former boss at Old Trafford this summer.
'He [Mourinho] likes me a lot and I like him a lot as a coach and as a person. He has put his trust in me and in my work, and I was very grateful to him', the Brazil international said.
Though he admitted a move was possible after his agent spoke to the Red Devils, he finally opted to remain with the Premier League champions.
'Manchester came to me, they talked with my agent, but nothing happened, because Chelsea would not negotiate me in any way and I'm very happy at Chelsea'.
He went on to compare Conte and Mourinho, who he believes are among the best in the world. 'They are very different. Everyone has their way of working. Mourinho is a coach who likes more the ball practice, works the ball possession and makes short games'.
'Conte likes to work the tactical and the physical part. Every coach has his way of working. Mourinho is a fantastic coach and won everything wherever he went', he added.
'Conte is a fantastic coach too, because he won everything at Juventus and has already won the Premier League in his first year with Chelsea. Each one has his merits'.