Goals from Gonzalo Higuain and Jose Callejon secured a 2-0 win for Napoli over 10-man Atalanta to move Rafael Benitez's side three points clear of their fellow title challengers in Serie A.
Earlier Saturday, champions Juventus spurned the chance to go provisionally top after missing several late chances in a 1-1 draw away to Inter Milan.
It gave Napoli, who started their third match of the campaign top on goal difference, the chance to pull clear of four other teams who had taken maximum points from their first two games of the season.
And despite Atalanta enjoying the lion's share of the scoring chances in the first half at the San Paolo, Higuain sent Napoli on their way to victory with a well-taken individual effort in the 71st minute.
Atalanta were reduced to 10 men a minute later when former Napoli player Luca Cigarini was shown a second yellow card for a brutal tackle on Callejon.
Barely 10 minutes later, Spanish striker Callejon finished off good work by Lorenzo Insigne to virtually secure the points for the Neapolitans.
Napoli, runners-up last season, now lead Inter and third-placed Juventus by two points ahead of the rest of the programme on Sunday, when Fiorentina would have to enjoy a goalfest against Cagliari if they were to dislodge Benitez's men.
Benitez was quick to play down Napoli's title hopes.
"The championship is decided at the end of the season, not after three games," said the Spaniard, whose side host Borussia Dortmund in their opening Champions League group game on Wednesday.
"We still have things to improve and we need to be ready for our next game."
Roma, the only other team to win their opening two games, are not in action until Monday when they visit Parma.
In Saturday's other late game AC Milan, who suffered defeat in their opening game of the campaign away at promoted Verona, looked to be heading for another 2-0 reverse until a dramatic, late fightback at Torino.
Danilo D'Ambrosio gave Torino the lead, which was doubled by Alessio Cerci 71 minutes.
Milan, however, began a most unlikely comeback in the 87th minute when Sulley Muntari's low shot sneaked into the Torino goal as confusion reigned in the home end.
In injury time, the Rossoneri were handed a lifeline when the referee pointed to the spot after Giovanni Pasquale's late foul on Andrea Poli in the box.
Although Milan coach Massimiliano Allegri could not watch, Mario Balotelli soothed fears when he stepped up and beat Daniele Padelli at the goalkeeper's right-hand post to secure a share of the points.
Earlier Saturday, Inter overcame a shaky first half against Juve to grab a 73rd-minute lead through Mauro Icardi, two minutes after the Argentinian substitute had entered the fray.
However, the Nerazzurri's bid to go top was halted in spectacular fashion when Arturo Vidal levelled only two minutes later and the hosts were lucky to escape with a share of the points as Juve missed three clear chances late in the match.
Inter coach Walter Mazzarri was pleased but admitted he lost control after Juve's quick equaliser.
"The boys didn't really get into the game in the first half but I liked the way we came out after the interval," said the former Napoli handler.
"We started to control things and took the lead, then we made a few mistakes and let Juve come back into it. That angered me a little."
While Mazzarri waved off suggestions his side could be one of several teams aiming to stop Juve winning a third successive title, a feat they last achieved in the 1930s, Juve Antonio coach Conte believes otherwise.
He said the result "shows that Inter can have title-winning pretensions".
A near-capacity 79,343 fans packed the San Siro and Conte added: "My side played a great game at a difficult ground against a team that can challenge all the way this season, especially as they have no Cup or European commitments."