كتب : Hatem Maher
The Brazilian keeper was helpless against a tamed shot by the Argentinean midfielder as the Nerazzurri secured a precious win.
Milan grabbed the lead through an Andrea Pirlo free-kick before Julio Cruz equalized for the Serie A holders.
Inter maintained their position on the league's summit, seven points clear of second-placed Roma. Milan are still struggling as they lie 12th on 18 points.
Pirlo put the Rossoneri ahead from a trademark free-kick on the edge of the area after 17 minutes.
The dead-ball specialist superbly curled the ball over the wall and past the motionless Julio Cesar.
Inter pressed forward after conceding the opener while Milan tried to hit on the break.
Inter's Argentinean defender Walter Samuel was replaced by Marco Materazzi in the 33rd minute after sustaining an injury.
The in-form Cruz leveled the score three minutes later to take his tally to ten goals this season.
The Argentinean frontman collected Cambiasso's low cross inside the area before rifling home at the near post as he was surrounded by three ineffective defenders.
Dida should have done better to parry the shot which looked to be within his grasp.
Javier Zanetti could have put Inter ahead shortly after when his powerful drive went just wide of the post.
Inter made amends three minutes past the hour mark, thanks to a Christmas gift by Dida.
Serginho was too lazy to control Paolo Maldini's header and Cambiasso capitalized to send a shot that looked to be going straight to Dida's hands.
The former Corinthians keeper needlessly dived the wrong way and the ball went into the back of the net.