Manchester City manager Roberto Mancini has urged midfielder Samir Nasri to improve his performance.
The Italian says that the 25-year-old is "a top, top player" but claims that there is still room for improvement in the Frenchman's game.
"In my opinion we are talking about a top, top player here," he said. "And if he wants he can change every game. But I think he can do better.
"He has played some good games for us but he can do better because he has everything. No, I don't think he has struggled [since joining City from Arsenal in 2011].
"When I say this, we are talking about a player like [Yaya] Toure or [David] Silva – we always think they can change every game they play because they are capable of doing that."
Mancini added that he has confidence in Nasri's potential and said that the player has recovered from his recent calf injury.
"But sometimes in spells when we are playing a lot of games in a short space of time – like at the moment – a player can be tired," he continued.
"Samir also had a problem with his calf in the last two games but I wait for him to play always a fantastic game because he can do this."
City will host Everton at the Etihad Stadium in the Premier League on Saturday.