The former Blues midfielder says that Kante's performances have dipped over the past season due to him being utilised away from his preferred role as a rampaging defensive shield.
Speaking to Goal, Poyet said: “In very important games Lampard went with Kante, Jorginho and [Mateo] Kovacic until the last month with injuries.
“Those are the three most experienced players who played under Sarri but now they play with more freedom, especially in Jorginho having more possibilities to move around to go sideways and forward. Last year, he was very static. There are plenty of options.
“In Kante's first year, he came to Chelsea and I made it public that he is the best central midfielder in the world. After a previous season as a number eight in that different position, we lost how important and unique he was as a player.
“I hope he can get back to that. In his best position, he is unique and there's not many players that can give you what he can do right now."