Flamini has played twice since arriving back in London - he's been booked in both games - but Wenger says he's exactly what Arsenal needed.
He said: "[He is] absolutely crucial to the balance of the team.
"He has done very well. He had not played since May and when you see how well he came in, it shows you how well, how focused and how dedicated he was in his preparation.
"He's got what is needed in every team."
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