Thiago Silva and Luca Antonini are not even in the squad making the trip to Bari, so Milan must completely revamp their defence.
The two players picked up knocks during the midweek 2-2 draw with Real Madrid in the Champions League.
Daniele Bonera and Massimo Oddo are already out of action due to long-term injury problems.
This has forced Coach Massimiliano Allegri to recall Marek Jankulovski, who had been dropped and is expected to leave in January.
Uruguayan youth team defender Bruno Montelongo is also brought along in a desperate bid to make up the numbers.
Oguchi Onyewu is still out of contention after a year-long injury lay-off and this week's training ground brawl with Zlatan Ibrahimovic.
Milan squad: Abbiati, Amelia, Roma; Jankulovski, Montelongo, Nesta, Papastathopoulos, Zambrotta, Yepes; Abate, Ambrosini, Flamini, Gattuso, Pirlo, Seedorf; Ibrahimovic, Inzaghi, Pato, Robinho, Ronaldinho