Atalanta walloped AC Milan 5-0 courtesy of goals from Lombardy Derby, Josip Ilicic, and a Papu Gomez.
Atalanta was able to overcome Milan in the Derby di Lombardia after a good preparation without Champions League pressure, after qualifying for the Round of 16.
On their return, Papu Gomez and Josip Ilicic were too handy for the visitors in the absence of Duvan Zapata who has been out for a long-term but were on a roller coaster.
The Rossoneri also had their own to contend with as Theo Hernandez and Lucas Paqueta serve suspension, and Pioli dropped Krzysztof Piatek for Rafael Leao.
In the final game before Christmas that Atalanta donned their traditional green ‘tree’ kit, which will be auctioned for charity.
Gianluigi Donnarumma got into early save under 45 seconds after palming away an Ilicic curler with the weaker right foot.
Alejandro Gomez opened the goals account with a superb solo effort after bursting down the left flank, nutmegging Andrea Conti and smashed it right-footed into the far top corner from an acute angle.
The host stepped up their game when they doubled when Robin Gosens ran down the left, cut inside and his cross-shot which took a slight deflection off Pasalic from six yards to wrong-foot Donnarumma but the former Milan midfielder refused to celebrate as a show of respect for his old club.
The host made it three when Ilicic turned Davide Calabria inside out to blast in with his weaker right foot across Donnarumma into the far corner.
Ilicic got his double curling a trademark left-foot stunner into the far top corner from the edge of the box. This was the first time since 1955 that Atalanta will score four goals against the Rossoneri in Serie A.
They put the icing on the cake when substitute Luis Muriel through a long ball deposited the ball into an empty net giving Milan their heaviest defeat since Roma in 1998.
Atalanta starting line up: Gollini; Toloi, Palomino, Djimsiti; Castagne, De Roon, Pasalic, Gosens (Hateboer 89); Ilicic (Muriel 79), Malinovskyi; Gomez (Freuler 88)
Milan starting line up: G Donnarumma; Conti, Musacchio, Romagnoli, Rodriguez (Calabria 46); Kessie, Bennacer, Bonaventura (Piatek 64); Suso (Castillejo 84), Leao, Calhanoglu
Written by: Mojeed Oladipupo