Napoli survived a late Sassuolo surge to ease the pressure on under-fire boss Rafael Benitez with a 1-0 win.
Juventus defended their place at the top of Serie A with Arturo Vidal on target twice in a 3-0 win over Cesena.
Fiorentina twice hit the woodwork and missed other chances and had to settle for a goalless draw against Sassuolo.
Sampdoria keeper Emiliano Viviano came to to rescue as Sassuolo threatened to condemn them to a first defeat.
Sassuolo forward Domenico Berardi has been banned for three Serie A games for aggressive conduct towards Juan Jesus.
AC Milan edged a nine-goal thriller with Parma at the Stadio Tardini to join Juventus and Roma at the top of Serie A.
Live only on