Zlatan Ibrahimovic maintained his scoring run with a goal in each half to help Milan earn a 3-1 win over 10-man Napoli that takes his side back to the top of Serie A.
Sassuolo moved to the summit earlier on Sunday with a 2-0 win at Hellas Verona but Milan responded with an Ibrahimovic-inspired victory at Stadio San Paolo to go two points clear.
The veteran striker headed in from 14 yards with 20 minutes played to score for the eighth league game running before kneeing in an unorthodox second after 54 minutes, but he worryingly limped off late on with a thigh injury.
Dries Mertens had responded for Napoli only for Tiemoue Bakayoko to be sent off 165 seconds later and Milan, without head coach Stefano Pioli and a number of other backroom staff members due to coronavirus, wrapped up the win through Jens Petter Hauge's debut Serie A goal in injury time to maintain their unbeaten start.
Napoli XI: Mertens, Manolas, Insigne, Mario Rui, Koulibaly, Bakayoko, Di Lorenzo, Politano, Meret, Lozano, Fabian Ruiz
Subs: Llorente, Ospina, Maksimovic, Demme, Malcuit, Ghoulam, Zielinski, Lobotka, Petagna, N. Contini Baranovsky, Elmas
Milan XI: Ibrahimovic, Kjaer, Calhanoglu, Rebic, Romagnoli, Calabria, Kessie, Bennacer, Theo, Donnarumma, A. Saelemaekers
Subs: Tatarusanu, Antonio Donnarumma, Conti, Castillejo, Krunic, Dalot, Gabbia, Brahim, Duarte, J. Hauge, Tonali, L. Colombo