Nkunku admits he didn't see eye to eye with the now Chelsea manager.
He recalled to Canal+: "Why did I leave PSG? The arrival of (Thomas) Tuchel made me think.
"The fact of starting a season without really knowing what role you are going to have is quite complicated.
"There comes a time when you come to the end of your contract and you have one year left, either you extend or you leave, I made the choice to simply leave."