Per Mertesacker has said that the Arsenal squad cannot just be "peace and pancakes" when asked about his recent on-the-field row with teammate Mesut Ozil.
The Germany defender appeared to criticise his compatriot for failing to applaude the travelling supporters in the 6-3 defeat to Manchester City a fortnight ago.
However, Mertesacker, who played with Ozil at Werder Bremen, believes that total tranquility within the squad is not healthy in the development of the team.
He told Bild: "It can't just be all happiness, peace and pancakes. If it is then you won't develop as a team.
"The good thing is that Mesut and I know each other well from our time at [Werder] Bremen. We can be honest with each other."
The Gunners host Cardiff City on New Year's Day.
