During his pre-match news conference, Allegri alluded that Pulisic would not be available for the weekend fixture at San Siro.
"Pulisic is unlikely to play, although there are still two days until the match and anything can happen," Allegri said.
The Rossoneri have moved quickly to adjust their tactical approach, with Christopher Nkunku partnering with Rafael Leão in attack. The Frenchman has only started two Serie A games so far this season and will look to make an impact in a rare starting opportunity. Leão scored the game-winner in 51st minute.