Roma maintained its perfect start to the Serie A season with a 2-0 win at Sampdoria on Wednesday and took sole lead of the table after Napoli was surprisingly held to a 1-1 draw at home to Sassuolo.
Two-time defending champion Juventus' abject start to the season continued as it had to come from behind for a controversial 2-1 win at Chievo Verona, while AC Milan again scored twice in the dying minutes to draw 3-3 at Bologna.
Mehdi Benatia scored a stunning first goal in Italian football for Roma and Gervinho sealed the result. The capital club has won its opening five matches and moved two points clear of Napoli and Juventus.
Elsewhere, Lazio bounced back from its derby defeat to Roma to beat 10-man Catania 3-1.
In other results it was: Parma 4, Atalanta 3; Torino 2, Hellas Verona 2; and Livorno 1, Cagliari 1.
Napoli had won its opening four matches, while Sassuolo was the only team without a point in Serie A and was still reeling from a 7-0 defeat at home to Inter Milan on the weekend.
Napoli took the lead in the 15th minute when a cross was cleared straight at Blerim Dzemaili, who lashed it into the bottom left corner from 25 yards.
Sassuolo had scored just one goal in its opening four matches and Simone Zaza was again the scorer five minutes later, firing into the roof of the net from a tight angle following a Jasmin Kurtic through ball.
And Sassuolo held on for its first ever Serie A point.
The result means that Roma is the only team still with a perfect record following its victory against Sampdoria.
Roma was struggling to break down a resilient Sampdoria defence and Rudi Garcia's frustration got the better of him as he was sent to the stands 10 minutes into the second half for his protests.
Benatia broke the deadlock 10 minutes later with a wonderful solo effort. The Morocco striker wove his way through the Sampdoria defence, beating four players on his way into the penalty area. He then tripped but fired home as he fell.
Gervinho also scored his first Serie A goal after he was sent clear by Francesco Totti, two minutes from time.
Sampdoria winger Antonino Barilla was sent off for a second booking in stoppages
Milan was unbeaten at Bologna since 2002 but had endured a miserable start to the season with just four points from as many games and was missing the suspended Mario Balotelli as well as a number of injured players.
It took the lead in the 12th minute when Andrea Poli fired Robinho's smart pass across goal into the bottom left corner but Diego Laxalt levelled for Bologna in the 33rd following a swift counter.
Milan missed a series of incredible chances and Laxalt — who is on loan from the Rossoneri's bitter rival Inter Milan — headed in Lazaros Christodolopoulos cross seven minutes into the second half to put Bologna in front.
Cristaldo also celebrated his first Serie A start with a goal, extending Bologna's lead shortly after the hour with a diving header into the bottom right corner following Alessandro Diamanti's cross.
Phillipe Mexes had a shot crash off the crossbar and it seemed as if Milan was heading for a third defeat of the season.
However, Milan had recently come back with two late goals at Torino to secure a draw and it did so again. Robinho pulled one back in the 89th and played a part in the equalizer two minutes later. The Brazilian's header was saved but the rebound ricocheted to Ignazio Abate to snatch a share of the points.
Juventus struggled to carve out opportunities in Verona and Chievo took a shock lead in the 27th minute.
Italy goalkeeper Gianluigi Buffon made a rare mistake, clearing a ball straight to Gennaro Sardo, who crossed in for Cyril Thereau to fire into the bottom left corner with a side-footed volley.
Juve levelled less than two minutes after halftime. Chievo goalkeeper pulled off a fantastic save to parry Fabio Quagliarella's header from Paul Pogba's cross. Quagliarella then drove the follow up onto the crossbar but eventually managed to scramble it into the back of the net.
There was controversy three minutes later. Another mistake by Buffon saw him only parry Simone Bentivoglio's shot. Alberto Paloschi fired in the rebound but was harshly ruled out for offside, sparking furious protests. The assistant referee had appeared to mistake Paloschi for Thereau who had been in an offside position.
Juventus took the lead in the 65th when Alessandro Bernardini dived onto Pogba's cross and turned it into his own goal.
In Rome, Lazio went in front in the fourth minute when Mariando Andujar spilled Antonio Candreva's free kick and Ederson slotted in the rebound from six yards.
However, its lead lasted less than a minute before Lorik Cana kicked his clearance straight at Pablo Barrientos, who raced into the area and fired in the equaliser.
Yet another defensive mistake saw Lazio take the lead shortly before halftime when Senad Lulic pounced on Tiberio Guarente's misplaced pass, raced downfield and drilled into the bottom right corner.
Catania defender Giuseppe Bellusci was sent off on the hour and Hernanes sealed Lazio's victory in the final minute.