Abbiati disappointed with Leonardo switch
The Brazilian will be in the Nerazzurri dug-out for the top-of-the-table clash, a season on from when he was in the opposite camp as Milan's coach.
After leaving the current leaders at the end of last season, he made a surprise return to the game as Inter's coach at Christmas, and has sparked a revival of their title challenge.
"The fact that when he left he made us understand that he wouldn't be coaching the following year left me perplexed," Abbiati told Sky Italia.
"I think his passage to Inter has disappointed many Milan fans. Some of my team-mates were also hurt by the decision."