Arkadiusz Milik bagged an early brace for Napoli and Jose Callejon neutralised a comeback from nine-man Milan in this 4-2 thriller.
The Partenopei fought back from 2-0 down to draw at Pescara in the opening round, but made many changes, drafting in Arkadiusz Milik and Dries Mertens, while Jorginho returned from suspension. The Rossoneri beat Torino 3-2 thanks to a Carlos Bacca hat-trick and last-gasp Gianluigi Donnarumma penalty save. Gustavo Gomez got his debut after stepping in for banned Gabriel Paletta.
Ignazio Abate missed a sitter after eight minutes, ballooning over from six yards at the back post from a smart M’Baye Niang assist.
Alessio Romagnoli flicked in a deflected Niang shot with his heel, but the centre-back was offside.
Mertens curled a sensational effort from the outside left corner of the box and it bounced off the far post, into the path of Milik to tap in on his first Serie A start. The Poland international got off the mark with his first competitive goal in a Napoli jersey.
Mertens was just trying to get his bearings and another wonderful curler from almost the same position was denied by an equally fantastic Donnarumma fingertip save at the far top corner.
The pair clashed again, a Mertens strike from the other side right-footed that Donnarumma palmed away and the Milik follow-up was charged down. However, on that same corner Milik soared above the crowd for a towering header to double Napoli’s lead.
Mertens was unstoppable and another shot was deflected away from Milik after trapping a long ball.
Niang hit the side-netting after the restart and it was a warning, because he ran on to a Suso slide-rule pass and smashed the angled drive across Reina into the far bottom corner.
The tension got to Napoli, as Coach Maurizio Sarri saw red for dissent and moments later Suso completed the turnaround by hammering a strike under the bar from the edge of the box.
Jorginho had a couple of volleys charged down and it turned into end to end stuff with two exhausted sides trading punches.
Mertens was in the thick of it yet again, his curler palmed away by Donnarumma, but Mattia De Sciglio was too slow to react and Callejon tapped in at the far post.
Moments later Milan lost the plot, as Juraj Kucka was booked for a push on Mertens and immediately received a second yellow card for swearing at the referee.
Jose Ernesto Sosa and Gianluca Lapadula made their Rossoneri debuts, but Niang received an idiotic second yellow card for standing in front of Reina to stop him taking a goal kick, reducing Milan to nine men.
There was time for one more ridiculous moment, as Lorenzo Insigne rolled across for Callejon and in an attempt to clear it off the line, Romagnoli accidentally punched it into the net for 4-2.
Sent off: Kucka 75 (M), Niang 88 (M)