The former Juventus man was not considered for his debut against Manchester United before the international break, although there was hope that he would be involved against Nottingham Forest at the weekend.
Slot revealed before the game that Chiesa had joined in with a few training sessions, but he suggested that he would side with players who were operating at 100% fitness as opposed to the 26-year-old.
With Chiesa absent from the ranks, Liverpool slumped to a shock 1-0 loss against the Tricky Trees, but the Italy international has boarded the plane back to his homeland for Tuesday's showdown with Milan.
Chiesa should therefore be in contention for his first appearance for the six-time European champions against the Rossoneri, whom he has scored three goals and provided four assists against in 13 previous Serie A appearances.
However, the Euro 2020 winner has failed to score or assist in his most recent five appearances against Milan, most recently netting a brace for Juventus during the 2020-21 Serie A season.
Are there any surprises in Liverpool's Champions League squad?
Chiesa is one of 23 Reds men on the plane to Italy, and the only notable absentee is Harvey Elliott, who faces several more weeks on the sidelines with the foot fracture he sustained during the international break.
Curtis Jones and Alexis Mac Allister both battled back from knocks in time to appear in the loss to Forest, and having come through unscathed, both midfielders are also in the squad for Tuesday's game.
Third-choice goalkeeper Vitezslav Jaros has also travelled to Milan, and the only real eye-catching inclusion apart from Chiesa is 21-year-old defensive midfielder Tyler Morton.
The England youth international was heavily linked with an exit in the summer and is yet to play a single minute of competitive football under Slot, but he could now provide an alternative option in the number six role.
Could Slot make any changes against Milan?
The manner of Liverpool's loss to Forest at the weekend was incredibly disheartening, as Slot's men were customarily dominant in possession but just failed to make the most of their chances when they came.
Slot has started Mohamed Salah, Diogo Jota and Luis Diaz in each of Liverpool's first four Premier League games of the season, but Cody Gakpo and Darwin Nunez will be pushing for starts at San Siro, despite failing to impress off the bench on Saturday.
While Chiesa is a viable option to replace Salah, any debut for the Italy international will surely come as a second-half substitute, as Slot has been extremely careful over his fitness so far.
Should the Dutchman also adopt a similar approach with Mac Allister following his knock on international duty, Wataru Endo could come in alongside Ryan Gravenberch in the engine room, potentially allowing the latter to play a bit further forward.
Liverpool squad for AC Milan Champions League clash:
Alisson, Gomez, Endo, Van Dijk, Konate, Diaz, Szoboszlai, Nunez, Mac Allister, Salah, Chiesa, Jones, Gakpo, Jota, Tsimikas, Robertson, Gravenberch, Jaros, Kelleher, Alexander-Arnold, Quansah, Morton, Bradley