Leicester boss Claude Puel has questioned whether Eden Hazard would need to leave Chelsea to become the best player in the world.
The Foxes chief gave Hazard his professional debut when he was a 16-year-old at Lille in 2007.
Hazard has starred for Chelsea since moving from Lille in 2012, winning the Premier League twice, and has been linked with a move to Real Madrid.
The Belgium international has been quoted as saying he is ready to sign a new deal at Stamford Bridge.
Yet, ahead of their reunion when Leicester travel to Chelsea on Saturday, Puel remained unsure over Hazard's long-term future.
Puel said: "He can continue to make progress. After, I don't know if he has to stay at Chelsea or not -- is that a problem?
"But I think he can continue to develop as a player. He has all the qualities to play for all the great teams in Europe, of course.
"He can make the difference, so for me he is a top player in Europe.
"The team is around Eden because he is the most important player for them. It is not possible to stop him because he cannot play in just the same position.
"He can play wide or striker or come back to take the ball. He can make always penetration and the difference, it is just important to have a good structure and organisation around him.''
Hazard has also won the EFL Cup and Europa League at Stamford Bridge while also being named the Premier League Player of the Year in 2015.
But Puel could always see the player's ability when the pair were together at the Metropole.
"He is a fantastic player and he improves a lot,'' he said. "But he had the same quality at 16 when he started in the first team at Lille, it was the same.
"Of course now he has more consistency in his game but always he is fantastic in his play and has the ability and capacity to make good penetration and give good assists.
"Eden is a fantastic player but I wouldn't man-mark him.
"If we just keep concentration on Eden, other players can make the difference also. A good response is always a collective response with a competitive organisation.''