AC Milan have signed midfielder Sulley Muntari on loan from Inter Milan until the end of the season. The Ghanaian international, who becomes a free agent in the summer, has made just four league appearances for i Nerazzurri this season. A statement from AC Milan read: \"AC Milan announces it has acquired Sulley Muntari on a temporary loan.\" Milan opted to make a move for the 27-year-old after losing midfielder Alexander Merkel last week to a knee injury for two months. Merkel only returned to Milan earlier this month in joint ownership from Genoa with i Rossoneri facing a shortage in midfield due to the injury problems of Mathieu Flamini, Gennaro Gattuso and Alberto Aquilani. Former Sunderland player Muntari becomes i Rossoneri\'s fifth reinforcement in the winter transfer market and their second of the day after teenage Austrian striker Philipp Prosenik joined from Chelsea.