AC Milan won 2-0 against visiting Fiorentina on Sunday to open a five-point lead at the top of the Italian Serie A.
Second-place Inter Milan, on 18 points, are ahead of Sassuolo on goal difference after beating them 3-0 on Saturday, when champions Juventus were held 1-1 at promoted Benevento and slipped six points from the top.
Milan defender Alessio Romagnoli nodded in a corner kick and Fiorentina striker Dusan Vlahovic hit the stick's junction before German Pezzella's foul on Alexis Saelemaekers led to a spot kick converted by Franck Kessie.
The Ivory Coast midfielder took another penalty after Martin Caceres brought down Theo Hernandez, but was denied by Bartlomiej Dragowski.
After the break Hakan Calhanoglu hit the post as the Devils stayed in control despite missing their injured veteran ace Zlatan Ibrahimovic, who leads the scorers' chart on 10 goals.
Former Milan defender Daniele Bonera led the squad to clinch two wins and a Europa League draw since taking over from head coach Stefano Pioli and his assistant Giacomo Murelli, who went into isolation with coronavirus infection, while Cesare Prandelli has now lost both games since taking over the Florentines.
"I saw another piece in the puzzle we have begun some time ago," Bonera said. "The third game played in a week is always the toughest and we saw it today against Fiorentina, but we played as the great team we are.
"We had a video call with Pioli in the changing room and he complimented us. But he is always with us, also when we train."
A late classic pitting Napoli against lacklustre Roma saw the Naples hosts win 4-0 as they wore a striped shirt resembling that of the Argentina national team to honour their former ace Diego Maradona, who died Wednesday in his native country.
Skipper Lorenzo Insigne curled in a textbook free-kick and celebrated by displaying and kissing a number 10 shirt with Maradona's name.
Fabian Ruiz' drive, a Dries Mertens tap-in and Matteo Politano's devastating run after the break sealed a win that put the Neapolitans level on 17 points with Juventus and Roma.
The day opener saw Lazio lose 3-1 at home to understrength minnows Udinese, failing to repeat their recent good display in the Champions League.
The Romans, who defeated Zenit St Petersburg 3-1 in midweek, followed the fate of Atalanta who won 2-0 at Liverpool only to lose by the same scoreline to Verona on Saturday.
"We were cocky and lacked humility, despite knowing what kind of game Udinese were going to play," Lazio boss Simone Inzaghi said. "We are all responsible, I the first. We missed something that we failed to display on the pitch."
Australian Associated Press