Andre-Frank Anguissa was the hero for Napoli on Saturday with the last-gasp winner which gave the Serie A champions a 1-0 success over Cagliari, while Roma saw off promoted Pisa by the same score.
Cameroon midfielder Anguissa struck in the fifth minute of stoppage time just as it looked like Antonio Conte's team would fail to break down dogged Cagliari.
Just moments before, Scott McTominay had wasted a golden opportunity to snatch the points at the Stadio Diego Armando Maradona where the hosts had few clear chances on goal.
"It was a hard match because they defended really well but we didn't leave anything out there, we pushed and in the end we won," said Anguissa to DAZN.
A year ago almost to the day Anguissa netted a winner in added time against Parma, but he scoffed at suggestions Saturday's strike was a good omen for Napoli's bid to successfully defend the Scudetto for the first time.
"The most important thing is winning, we played as a team and that's how it should be," Anguissa said.
The closest Napoli came to breaking the deadlock before stoppage time came in the 57th minute when Cagliari goalkeeper Elia Caprile pulled off a one-handed save to stop Leonardo Spinazzola's low drive fizzing in at the near post.
Stars Kevin De Bruyne and McTominay were subdued, while Lorenzo Lucca was again ineffective as a replacement for injured Belgium striker Romelu Lukaku.
Napoli are set to sign Rasmus Hojland from Manchester United with the Denmark striker landing in Italy on Saturday ahead of an initial loan move with obligation to buy.
Roma continued their positive start to life under Gian Piero Gasperini with their narrow win in Tuscany, Matias Soule deciding a tough contest nine minutes after half-time.
Soule stroked home Evan Ferguson's lay-off to give Roma a perfect six points, level with Napoli -- who lead on goal difference -- and Cremonese.
The Argentine had the ball in the net for a second time shortly after opening the scoring, but he was denied a brace from the raucous Arena Garibaldi when he was spotted handling the ball before shooting past Adrian Semper.
"Every day that I'm here with the faith that is shown in me I feel better, but I can still give more," said Soule, who shone alongside countryman Paulo Dybala.
"I'm always with him, so we have a connection off the field as well. When he's on the pitch he gives us something more."
Riccardo Orsolino celebrated his selection by new Italy coach Gennaro Gattuso by guiding home the only goal of Bologna's 1-0 win over Como.
Winger Orsolini met Santiago Castro's low cross just before the hour to give Bologna their first win of the season, suggesting he is set to carry on with the fine form which helped Vincenzo Italiano's team win the Italian Cup last season.
The 28-year-old struggled for playing time with Italy under former coach Luciano Spalletti, who was sacked in June following a troubled start to the Azzurri's World Cup qualifying campaign.
"I need to get to know the coach (Gattuso) but I'm there for him and the rest of the lads. I'm always ready," said Orsolini.
Atalanta are without a win under Ivan Juric after Patrick Cutrone gave Parma a 1-1 draw.
Cutrone's 85th-minute strike cancelled out a fine finish six minutes earlier from Mario Pasalic who was playing 300th match for Atalanta and was a key figure in the team which won the Europa League under Gasperini last year.
