Manchester City midfielder Nigel de Jong fears the talent of team-mate Mario Balotelli will go to waste if the striker does not change his ways.
The 20-year-old Italian this weekend angered boss Roberto Mancini, who hauled the striker off after he attempted a trick shot in the club's friendly against Los Angeles Galaxy.
De Jong was particularly demonstrative in his remonstrations with Balotelli at the time and he admits that his team-mate is a frustration.
The Dutchman is quoted as saying by The Guardian: "I've played with some strange characters in the past but it's the first time I have seen that.
"It is frustrating, and he has to iron out those issues otherwise it will be a waste of his talent. He has to realise that now.
"All his team-mates are here to help him but he's his own person and he is the only one who can change his ways."