AC Milan's Theo Hernandez (left) and Roma's Chris Smalling vie for the ball during the Serie A soccer match between AS Roma and AC Milan at Rome's Olympic stadium, Sept 1, 2023. (PHOTO / AP)

ROME - Ten-man AC Milan beat AS Roma 2-1 thanks to goals from Olivier Giroud and Rafael Leao at Stadio Olimpico on Friday to move a provisional three points clear at the top of Serie A, spoiling Romelu Lukaku's debut for the home side.

Milan has a maximum nine points while Roma, with just one, continued its poor start and are winless in the opening three league games for the first time since 2011-12.

"The result is important, like the performance," Milan coach Stefano Pioli told DAZN. "It gives continuity to the first two and I'm satisfied."

The game was barely nine minutes old when striker Giroud put the visitors ahead by calmly converting a penalty after goalkeeper Rui Patricio had brought down Ruben Loftus-Cheek. The Frenchman has scored in six appearances in a row for the second time in his career in the big five European leagues

Milan thrashed Torino 4-1 in its home opener last weekend after kicking off the season with a 2-0 win at Bologna.

The game was barely nine minutes old when striker Giroud put the visitors ahead by calmly converting a penalty after goalkeeper Rui Patricio had brought down Ruben Loftus-Cheek.

The Frenchman has scored in six appearances in a row for the second time in his career in the big five European leagues, having done so in 2015 for Arsenal.

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Roma looked shaky as Milan went close to adding a second goal before the half-hour but Patricio showed great reflexes to keep out US forward Christian Pulisic from close range.

However, winger Leao extended Milan's lead three minutes after the break, firing Davide Calabria's lofted cross in off the post with an acrobatic first-time finish.

Roma failed to fire in front of goal even after Milan went down to 10 men in the 61st minute when defender Fikayo Tomori was shown a second yellow card for a foul on Andrea Belotti.

Roma's Jose Mourinho made a triple substitution 20 minutes from time with forward Stephan El Shaarawy making way for new arrival Lukaku, who joined on a season-long loan from Chelsea.

The Belgium striker, welcomed at the airport by about 4,000 Roma fans when he landed on Tuesday, could have scored a minute after coming on but his first-time shot from the edge of the box sailed narrowly over the bar.

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Roma eventually pulled a goal back in stoppage time through Leonardo Spinazzola, while Nicola Zalewski had a chance to equalize in a hectic finish to the game but it was too little, too late to rescue a point.

Mourinho, back on the touchline after serving a 10-day ban for criticizing a referee at the end of last season, refused to attend the post-match press conference.