Reigning champions Juventus scored four goals in a stunning final 11 minutes to overcome a stubborn Udinese side 4-1 and open up a two-point lead at the top of Serie A on Sunday.
Juventus' emphatic victory coupled with AC Milan's 0-0 draw at Parma ensured the title-holders maintained their unbeaten run and took sole possession of first place in Italy.
European champions Milan have 21 points, two fewer than Juventus after nine matches played.
Roma, champions in 2001, drew level with Milan after beating arch rivals Lazio in an emotional Rome derby which only came to the boil in the final minutes.
Two moments of Brazilian magic gave Roma the edge at the Olympic stadium with Mancini's sublime back-heeled volley breaking the deadlock before his compatriot Emerson finished a lightning counter-attack with a fierce half volley.
Lazio's defeat ended a miserable week for Roberto Mancini's men whose Champions League hopes were dented on Tuesday following a 4-0 thrashing at home to Chelsea.
Juve coach Marcello Lippi hailed his players for a breathtaking comeback.
"It was a demonstration of quality," he said. "We were up against a well-organised, compact side, who were dangerous on the counter-attack. They had their chances but in the end we dominated."
Lippi said his squad was the strongest he had ever worked with.
"I've not trained a group of players with this much quality before," he added.
Marek Jankulovski gave Udinese a 66th minute lead from the penalty spot at the Delle Alpi stadium before Juventus' late blitz.
Marco Di Vaio headed in Lilian Thuram's cross to bring Juve level with the club's 4,000th goal in Serie A, before fellow second-half substitute Fabrizio Miccoli prodded home from close range to put the home side in front.
Di Vaio poached an easy second goal for his seventh of the season as Udinese fell apart and David Trezeguet rubbed salt into the visitors' wounds by slamming in the fourth in stoppage-time.
Juventus were even able to afford the luxury of a missed penalty by Alessandro Del Piero, returning from injury after two months out and celebrating his 29th birthday.
Milan came closest to winning in Emilia Romagna when Jon Dahl Tomasson's goalbound shot was brilliantly blocked by Parma defender Matteo Ferrari.
Milan coach Carlo Ancelotti said a draw was a fair result.
"We played well and had a few opportunities, but overall I have to be content with a point," he said.
"Parma are a talented young team and not many teams will come here and get a result."
Parma remain fourth on 18 points, two ahead of Inter Milan who reignited their title challenge with a comfortable 3-0 win at home to struggling Ancona.
Julio Cruz's unstoppable 20-yard free-kick put Inter on their way before second-half goals from Marco Materazzi and Christian Vieri secured the points.
Fabio Grosso's late equaliser gave Perugia a 2-2 draw at home to fellow relegation candidates Lecce, while Reggina were held 1-1 at home to Modena.
In the day's other match, Chievo were 2-1 winners at newly promoted Siena where Sergio Pllissier grabbed both goals for the Verona side.
On Saturday, Sampdoria plunged Empoli deeper into the mire after defeating the struggling Tuscans 2-0, while Brescia were held to a 0-0 draw at home to Bologna.
Defeat in Genoa left Empoli rooted to the bottom of the table on two points and still looking for their first win of the season.