Flamini has been in impressive form for Arsenal this season
AC Milan have completed the signing of Mathieu Flamini from Arsenal on a four-year contract.
The France international, whose deal at the Emirates ran out this summer, has passed a medical and agreed terms to stay at the San Siro until 2012.
The departure will come as a blow to Arsenal manager Arsene Wenger, who had offered the 24-year-old a new deal.
Flamini had been a key player this season, making 39 starts in midfield and scoring three times.
While Milan vice-president Adriano Galliani moved to play down fan fears that Flamini had been signed to replace Gennaro Gattuso, the player himself expressed his delight at the move.
Having spent three seasons drifting in and out of the Arsenal starting team, Flamini secured a place in central midfield alongside Cesc Fabregas, keeping Gilberto Silva out the team.
He also made his breakthrough at international level, winning his first cap in a friendly against Morocco last November.
But for all Flamini's importance to Arsenal, highlighted by a superb performance as they won 2-0 in Milan in the Champions League, Wenger had been forced to concede that the player could be tempted elsewhere.
Flamini's move to Milan will not be the first time he has left a manager disappointed.
He was a key player for Marseille, playing in the 2004 Uefa Cup final, but left for Arsenal without a transfer fee changing hands as he had yet to sign a professional contract.
At the time of his move to north London, Marseille coach Jose Anigo said: "He's a traitor - this is a beautiful treason."
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