Nice coach Lucien Favre has told German newspaper Tagesspiegel that his star striker Mario Balotelli must do more than just score goals.
Balotelli has hit 13 goals in 19 matches for the surprise Ligue 1 challengers, scoring twice as Lille were beaten 2-1 on Friday.
And Favre said he believed the former Manchester City, AC Milan and Liverpool striker felt "just fine" in the French top flight.
"Mario's a nice lad, we get along well," he said.
Asked about his success in dealing with an often temperamental player, he said: "You need to distinguish Balotelli the person and Balotelli the forward.
"He's a role model as a person, and regarding the forward... his goals definitely help us, and Mario's played really well in the past few games."
But he urged the striker to keep working to develop his game, adding: "Mario knows best where his weaknesses are.
"He needs to make more and better runs. Mario must work more if he wants the long-term respect of his teammates.
"Scoring goals is not enough in modern football."
He said his side's success this season, which sees them poised for Champions League qualification, was "a miracle."
"All the teams around us are investing hugely," he said. "That's why the qualification for the Champions League would be a miracle, and I will do everything to make it come true.
"There is nothing greater than the Champions League -- not even the World Cup."
Favre questioned the Premier League when the newspaper pointed out that the most expensive league in the world has one club in the last eight of each of the European competitions.
"I raise my hat to Leicester City, but I don't think it'll be enough against Atletico Madrid," he said.
"They lost their heart when N'Golo Kante moved to Chelsea. What does it say about a league when the champion collapses because one player leaves?"
He said Manchester United were favourites against Anderlecht but had failed to convince him, adding: "There's a lot of money in the squad, but not a lot of results.
"That's no criticism of Jose Mourinho -- the problems are elsewhere."
He said the priorities of the Premier League were "very questionable" with "everything subordinated to the TV contract" and added: "Sometimes, I get the impression that football only plays a minor role."
Favre added: "When I watch English league games, I ask myself: What do they do there, tactically speaking?
"I grant the English all the money in the world, but it's not about football. Take a look at what's happening internationally.
"Tottenham is ranked second in the league, but Gent eliminates them in Europa League. Manchester City travels to Monaco with a two-goal lead and gets eliminated. And Arsenal does not stand a chance versus Bayern Munich."
Meanwhile, Nice could move to re-sign Hatem Ben Arfa this summer if he chooses to leave Paris Saint-Germain, according to the club's president Jean-Pierre Rivere.