AC Milan continued their unbeaten start to their Serie A title defence with a 2-0 win over Bologna on Saturday as Tammy Abraham earned Roma a 1-1 draw at Juventus on Paulo Dybala's return to his old stomping ground.

Champions Milan eased to a routine win at the San Siro with goals either side of half-time from Rafael Leao and Olivier Giroud to go top on goal difference.

Stefano Pioli's side took full advantage of Inter Milan's lose at Lazio on Friday night to move a point above their local rivals.

"We're more concentrated and have more self-belief than in the past, we played with a real commitment to attacking and defending as a unit," Pioli told Sky Sport Italia.

"I's happy with our performance but I know we can still get better."

Milan are one of four teams locked on seven points, with Roma, Lazio and Torino -- 2-1 winners over promoted Cremonese.

Napoli will reclaim the summit should they win at Fiorentina on Sunday night, Luciano Spalletti's flamboyant side on a perfect six points after two stunning displays in their opening fixtures.

Leao gave the hosts the lead in front of over 60,000 fans with his first goal of the season, the Portugal winger fortunate to see his duffed shot squirm past Lukasz Skorupski in the 21st minute after good play by debutant Charles De Ketelaere.

The 23-year-old Leao, who has been linked with Chelsea, should have added to Milan's lead before the break, missing a one-on-one with Skorupski in first half stoppage time.

However, he set up Giroud's opening strike of the campaign in the 58th minute with a perfectly clipped pass which the France international guided home with a beautifully-placed volleyed finish.

Nicola Sansone smashed the upright 10 minutes later for Bologna who are hovering above the drop zone with a single point.

Andrea Pinamonti scored his first goal for Sassuolo after moving from Inter, rolling home following a defensive mix-up to give his new team a 2-2 draw at Spezia.

Jose Mourinho said he was "ashamed" of his Roma players' performances before they fought back to draw through Abraham's first goal of the season.

England international Abraham headed home from Dybala's knock-down in the 69th minute at the Allianz Stadium to maintain Roma's unbeaten record.

Mourinho used the vulgar Italian expression "culo" to describe their good fortune at being only a goal down at the break after being given a lesson by Juve.

Roma escaped Turin with a point despite being second best for long periods. Dusan Vlahovic put Juve ahead with a stunning free-kick after barely a minute.

"I told my players at half-time that I was ashamed of them... We can't come here and play like this," he said.

"We did absolutely nothing, it was pure luck. It was a very different team in the second half."

Massimiliano Allegri's side stay unbeaten on five points but will be disappointed to not have taken all three on Saturday.

The good result at a place Roma have an awful record also masks a poor display from Dybala, who appeared overwhelmed on his first appearance at Juve since leaving as a free agent in the summer.

The Argentina forward won five Serie A titles and four Italian Cups in seven years with the Turin giants and was warmly applauded by home supporters before the match.

However there were some boos and whistles from the stands when he was eventually substituted with 12 minutes remaining having helped deny his old team the win.