MILAN (Reuters) - Inter Milan made it four wins out of four Serie A games as they beat Chievo on Sunday, while champions Juventus won for the first time by overcoming Genoa and Francesco Totti scored his 300th competitive goal for AS Roma.
Mauro Icardi's first-half goal at Chievo, the Argentine's first of the season, gave Inter a 1-0 win and left Roberto Mancini's outfit as the only team with 12 points from their opening four games.
Juventus off the mark thanks to an unlucky own goal by keeper Eugenio Lamanna and a Paul Pogba penalty at 10-man Genoa after they had failed to win in their opening three games.
Totti, in his 24th season at his only professional club and a week short of his 39th birthday, helped Roma draw 2-2 with Sassuolo as they twice recovered to maintain their unbeaten record.
Napoli won their first league game of the campaign, and their first under new coach Maurizio Sarri, by thrashing Lazio 5-0, helped by two goals from Gonzalo Higuain, and one each from Allan, Lorenzo Insigne and Manolo Gabbiadini.
Torino's Fabio Quagliarella scored twice to earn a 2-0 win over Sampdoria, leaving them second with 10 points, while Fiorentina moved into third place with nine after a 1-0 win at newcomers Carpi.
Roma twice came from behind to earn a 2-2 draw at Sassuolo, leaving the two teams level on eight points behind Fiore, while Serie A debutants Frosinone slumped to their fourth straight defeat as they went down 1-0 at Bologna.
Chievo created more chances in the first half against Inter in a midday match played in hot sunshine in Verona but the home team were made to pay for hesitant defending which allowed Icardi to score out of the blue just before halftime.
"The main thing is we managed to get the win at a tough place like the Bentegodi, struggling and battling away against an in-form Chievo side who defend brilliantly," said Mancini.
"I'm happy with the way the lads played because it was very hot and Chievo kept everyone behind the ball. It wasn't easy."
Juventus enjoyed a huge slice of fortune at Genoa when Pogba volleyed against the underside of the bar from Roberto Pereyra's cross and the ball hit Lamanna on the chest and bounced into the goal.
Juve's task was made much easier after Genoa had Armando Izzo sent off one minute before halftime and Pogba's penalty, harshly awarded for a foul by Diogo Figueiras on Giorgo Chiellini, polished off the game with half an hour to play.
Roma were stunned by Gregoire Defrel's solo goal after 22 minutes at the Stadio Olimpico before Totti, left out against Barcelona in the Champions League on Wednesday, sprang into action.
Sassuolo goalkeeper Andrea Consigli sent an attempted clearance straight to Miralem Pjanic who found Totti and the veteran rolled the ball into the net.
Matteo Politano put the visitors back in front on the stroke of halftime but a brilliant Mohamed Salah volley early in the second half rescued a point for Roma.
(Writing by Brian Homewood in Berne; editing by Clare Fallon and Ken Ferris)