Substitute Patrick Cutrone scored a last-gasp winner to give AC Milan their first win of the season at their San Siro stadium with a 2-1 victory over Roma on Friday.
Franck Kessie had gotten AC Milan off the mark after 40 minutes with Cutrone sealing victory five minutes into injury time to hand Roma their first defeat in over three years at the San Siro.
Defender Federico Fazio had pulled Roma level 1-1 on the hour mark.
Roma's World Cup winner Steven Nzonzi and AC Milan's Argentine striker Gonzalo Higuain both had goals disallowed.
Both sides had been looking to put stuttering starts to the season behind them with Gennaro Gattuso's Milan losing 3-2 at Napoli last week despite leading by two goals.
Milan's opening game against Genoa at the San Siro had been postponed because of the bridge disaster in the western port city.
"There were huge regrets over the defeat to Napoli," said Gattuso.
"But it's only the second match of the season. I can't talk about a turning point after two games. I know how our lads work and that we still need to become a team in some areas."
Roma counterpart Eusebio Di Francesco made several changes from the side that drew 3-3 with Atalanta in Rome last Monday, but he conceded his tactics did not work.
"We lacked sharpness," said Di Francesco.
"We're conceding too many goals, make too many bad choices on the field and it's something we have to work on in training."
The hosts dominated the first half, with Kessie opening the scoring under the driving rain after Ricardo Rodriguez whipped a low ball towards the back post where the Ivorian had an easy tap in.
Davide Calabria had a chance for a second but fired over from an angle with Roma goalkeeper Robin Olsen clearing a Higuain effort.
But Fazio broke through for the equaliser on the hour mark, the Argentinian poking home his fifth goal for Roma from close range after he pounced on a poor Calabria clearance.
Higuain looked to have scored his maiden Milan goal since his loan move from Juventus this summer just minutes later, but it was ruled offside after consultation with VAR.
Nzonzi thought he had scored after a corner, but it was disallowed for a handling offence by the former Sevilla midfielder.
But in a frantic finale Higuain found a way through following a blundering pass by Nzoni which gave Milan a final chance with the Argentine setting up Cutrone who finished off to the delight of the 60,000 fans in Milan.
The match was also watched by the club's former Brazilian star Kaka along with new directors Leonardo and Paolo Maldini, also former club legends.
"It's only right that there is enthusiasm for those who wrote the history of Milan, but we mustn't think that the current squad should shoulder all that," said Gattuso.
"We must find our motivation by ourselves, on the training field every day. We can play good football this year, work with greater calm than last season and do good things.
"The club has given me a complete squad with strength in areas we didn't have before."
Roma -- third in Serie A last season -- have just four points from three games and risk losing ground on champions Juventus and runners-up Napoli, who both have maximum six points from two games.
Juventus play at Parma on Saturday with Cristiano Ronaldo looking to opening his scoring account in Serie A while Napoli play Sampdoria in Genoa on Sunday.