The England international sat out Saturday's 5-1 derby drubbing at the hands of Inter Milan through suspension, but he should slot straight back into the first XI in midweek.
However, Pierre Kalulu is expected to miss the Rossoneri's next few games owing to a thigh issue, while former Arsenal man Ismael Bennacer still faces another couple of months out after a knee operation.
With a fresh-legged Tomori back in the fold, Malick Thiaw should be sacrificed following a disastrous display against Inter, as Simon Kjaer holds his spot in front of number one Mike Maignan.
Alessandro Florenzi is an option for change at right-back, but Pioli should not consider demoting his captain Davide Calabria, while Lucas Hernandez is a shoo-in on the left-hand side of the backline.
An untouched midfield should see all of Ruben Loftus-Cheek, Tijjani Reijnders and Rade Krunic continue in their roles, although the former's ex-Chelsea teammate Christian Pulisic is certainly at risk of the axe.
The American was anonymous during his side's loss to Inter, so Samuel Chukwueze may be given a chance to impress in the forward line alongside Rafael Leao and Olivier Giroud, who combined for Milan's consolation goal at the weekend.
AC Milan possible starting lineup: Maignan; Calabria, Tomori, Kjaer, Hernandez; Reijnders, Krunic, Loftus-Cheek; Chukwueze, Giroud, Leao
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