The striker recently signed a four-year deal with the Rossoneri, shortly after captaining Spain to their fourth-ever success in the European Championships.
The former Real Madrid marksman has been allowed an extended period of rest following his international exploits with Luis de la Fuente's troops in Germany.
The absence of a marquee signing should allow 22-year-old Lorenzo Colombo to continue up front after he netted a brace in the 3-2 victory over Manchester City on Saturday.
Ruben Loftus-Cheek and Fikayo Tomori were not a part of Gareth Southgate's thinking for England this summer, however the ex-Chelsea duo are key to plans in Milan.
Alessandro Florenzi is a doubt for this clash after being replaced on the 40-minute mark against Pep Guardiola's side, meaning that Tommaso Pobega could be promoted to the starting XI.
Providing three assists between them from the flanks versus the Citizens, Samuel Chukwueze and and Alexis Saelemaekers are expected to cause problems down the wings once again in Chicago.
AC Milan possible starting lineup: Torriani; Calabria, Tomori, Gabbia, Terracciano; Pobega, Bennacer, Chukwueze, Loftus-Cheek, Saelemaekers; Colombo