Giacomo Raspadori made Napoli provisional leaders of Serie A with the late winner in Saturday’s 1-0 home win over Spezia.
AC Milan moved level on points with the leaders, after winning 2-1 at Sampdoria later in the evening despite playing almost the whole second half with 10 men.
In Naples, Italy forward Raspadori struck the decisive goal in the final minute of a stodgy encounter at the Stadio Maradona, putting Luciano Spalletti’s side one point ahead of Atalanta.
The 22-year-old swept home Hirving Lozano’s cross to net his first goal for Napoli on his second start after arriving on loan from Sassuolo last month.
“It’s a moment that will stay in my head and heart,” Raspadori told DAZN.
“I missed two chances which I should have scored but thankfully the team put me in the position to score and I kept my head.”
Raspadori was one of three signings made in quick succession by Napoli just after the season started alongside Giovanni Simeone and Tanguy Ndombele.
He lead their attack in the absence of starting striker Victor Osimhen after the Nigeria forward was ruled out until at least after the international break.
Napoli, who will lose their league lead should Atalanta beat promoted Cremonese on Sunday afternoon, will make his signing permanent next summer assuming he meets unannounced sporting objectives.
They are on a high after a strong start to the domestic season and thrashing Liverpool in the Champions League opener midweek.
They travel to Rangers on Tuesday before their first true title test against AC Milan at the San Siro next weekend.
Spezia sit 14th on five points after their third defeat from the first six games of the campaign.
In Genoa, Rafael Leao’s miss-control set up Junior Messias to give the visitors the lead after just six minutes.
Ten minutes later, Leao collected a yellow card for raising an elbow. He received another one two minutes into the second half when he attempted an overhead kick and caught Sampdoria centre back Alex Ferrari in the face.
Ferrari finished the match with a white bandage wrapped round his head.
Against 10 men, the initiative briefly swung to Sampdoria. Filip Djuricic levelled in the 57th minute when he flicked a near-post header past Milan goalkeeper Mike Maignan.
Milan hit back ten minutes later. Gonzalo Villar handled Olivier Giroud’s header from a corner. The Frenchman buried the penalty kick.
Sampdoria applied frantic late pressure but could not score. Frustrated coach Marco Giampaolo earned himself a red card for arguing on the touchline in added time as his team stayed 18th with two points from six games.
Another late strike from Marcel Brozovic gave Inter Milan a hard-fought 1-0 win over Torino to offer some relief from recent blues.
Simone Inzaghi’s side were staring at another poor result at the San Siro after derby defeat to AC Milan last weekend and a midweek lesson from Bayern Munich until Brozovic delicately dinked home the winner.
The Croatia midfielder met Nicolo Barella’s inswinging cross by lifting a superb finish over Vanja Milinkovic-Savic which moved Inter temporarily third.
“We were in difficulty, this win is very important. It’s a win for all of us, everyone who supports Inter,” said Brozovic to DAZN.
Defeat was harsh on seventh-placed Torino who played well and forced Samir Handanovic into a couple of good saves when the scores were still level.