Irrepressible leaders Juventus stayed eight points clear after coming from behind to beat Cagliari 4-1 away, their 11th successive league win, with forward Fernando Llorente scoring twice.
Third-placed Napoli also won convincingly, beating Hellas Verona 3-0 away with goals from Dries Mertens, Lorenzo Insigne and Blerim Dzemaili.
At the halfway point in the championship, Juventus have 52 points from 19 games, Roma 44 and Napoli 42.
(Reporting by Brian Homewood; Editing by Josh Reich)