Dries Mertens scored twice as Napoli beat Bologna 3-1 to reclaim top spot in the Serie A table from reigning champions Juventus.
Following a 2-0 Juve victory over Chievo on Saturday night, long-time leaders Napoli needed a quick response, but instead former Inter Milan striker Rodrigo Palacio gave Bologna a first-minute lead.
Bologna defender Ibrahima Mbaye obliged with the equaliser as he put through his own net in comic fashion just four minutes later.
Adam Masina fouled Jose Callejon to concede a penalty that Mertens tucked away eight minutes before the break and just before the hour the Belgian winger turned home an assist from Lorenzo Insigne.
Third-placed Lazio slipped further behind the top two after their six-game unbeaten run was ended by a 2-1 defeat at AC Milan.
Milan midfielder Giacomo Bonaventura scored the winner at San Siro, heading home a minute before the break to earn Gennaro Gattuso’s men a third successive victory.
Italy U21 forward Patrick Cutrone had earlier nodded Milan ahead before they were quickly pegged back by a fine finish from Lazio midfielder Adam Marusic.
Sunday’s shock result came at Fiorentina, where lowly Hellas Verona pulled off a 4-1 triumph that featured a double from Juve loanee Moise Kean.
In the early game, a last-gasp Alberto Paloschi header saw strugglers SPAL force a 1-1 draw with Inter, who had gone ahead early in the second half through a Francesco Vicari own goal.
Hellas and SPAL remain in the relegation zone despite positive results, but they will just be grateful they are not basement boys Benevento, who were thrashed 3-0 at Torino.
Elsewhere, Udinese shook off the dismissal of Samir to edge past Genoa 1-0 with a goal from Valon Behrami and Crotone and Cagliari shared the points from a 1-1 draw at Stadio Ezio Scida.