Manchester City manager Roberto Mancini has criticised the form of midfielder Samir Nasri, telling the Guardian "he has not been playing at his level".
Nasri, 25, signed for City from Arsenal for around £24 million in 2011 and helped the club lift the Premier League trophy during his first season at the Etihad Stadium.
But, having started 14 of City's 26 Premier League matches this campaign and scoring just once, Mancini has questioned the France international's desire to push on this term.
Mancini told the Guardian: "I think Samir has fantastic qualities. With his quality, he should always play well. Every game he could be the difference.
"A player of this quality could be one of the best players in Europe. But it's not happening.
"Sometimes a player thinks it's enough what they did the year before and doesn't understand that every day they should improve.
"If you are a top player you know you can improve until the last day of your career but sometimes you get players who think it is not important to work and this is their worst mistake.
"Samir can do better than this year. He is a top player but he has not been playing at his level."