Claudio Ranieri wants Leicester supporters to give N'Golo Kante a good reception when Chelsea visit on Tuesday.
Kante was the sole core member of Leicester's Premier League title-winning side to depart in the summer when he joined Chelsea in a £32m deal.
Tuesday's EFL Cup tie, live on Sky Sports 1, will see the France midfielder come up against old team-mates Jamie Vardy and Riyad Mahrez, both of whom signed new contracts with the champions rather than pursue moves elsewhere.
Ranieri said on the eve of the game: "I will give to him a very warm welcome back and I am sure also our fans they must appreciate what he did last season and give him a warm welcome.
"I will be very happy if our fans clap him at the beginning and afterwards he is an enemy.
"They must understand that when a big team arrives, it is difficult to say no. For this reason, I say thank you to Jamie Vardy and his family, and to Riyad when they decided to stay here. For us, it was important to maintain everybody.
"He was very important for us and I think he was even more important for us than at Chelsea because Chelsea have so many big players."
Ranieri's CV has similarities with that of Antonio Conte, his opposite number on Tuesday night: both have managed Chelsea and Juventus,
Ranieri was in charge at Inter during the season when Conte won the first of three successive Serie A titles with Juve, and the Leicester boss said: "He is a winner, but of course he needs time.
"The reality here is different than in Italy and his job is bigger now, but I think he can lift some trophies.
"You need to understand the league and your players. The players must understand him and how he manages and how he changes, what he wants. I watch a good Chelsea so far."