Mancini has been tracking the 21-year-old Hamburg star for some time and now looks set to finally get his man now that the English and German domestic seasons are over.
“We are quite close to signing him,” the City chief said. “Boateng is a good player, a young player and strong. He plays for the national team and there is a good chance to get him.
“He can play three different positions; central defence, right full-back or in midfield. If we find a player like that it is better for us.”
Boateng, the younger brother of Tottenham’s Kevin-Prince Boateng, began his career with Hertha Berlin before moving to Hamburg in 2007.
He won the first of his three international caps against Russia last October, but was sent off for a second booking.
Boateng is set to be the first of several new big-money arrivals at Eastlands this summer, although Mancini admits he is concerned that failure to qualify for the Champions League may hinder his search.