The European champions jumped out to an early 2-0 lead after Cameroon striker Eto'o chipped a pass to forward GoranPandev who opened the scoring in the 13th minute.
The replacement of winger GoranPandev - apparently injured - with defender Christian Chivu in the Inter line-up minutes before kick-off caught everyone by surprise, while the visitors' high-pressure tactics and gamesmanship continually frustrated the hosts.
Goran Pandev's 22nd-minute strike from long range failed to dip quickly enough to prevent it going over while Wesley Sneijder could only shoot harmlessly wide in the final minute of the half after a neat one-two with fellow attacker Milito.