MILAN (AP) — Inter Milan beat local rival AC Milan 1-0 in front of a sell-out crowd at San Siro to move top of Serie A on Sunday, as Mario Balotelli failed to make an immediate impact against his old club on his second debut for the Rossoneri.

"It was a bit of a strange derby as it's only the third round, the teams aren't at their best yet," Inter coach Roberto Mancini said. "We had character and we made the most of the few chances we got."

Fredy Guarin celebrated his 100th league appearance with a stunning goal after Milan had wasted a number of chances. Balotelli, who rejoined Milan on loan from Liverpool last month, hit the post and went close with a free kick.

"I can be happy because despite everything we didn't deserve to lose," Milan coach Sinisa Mihajlovic said. "We played well. We did everything we prepared in the week but we just lacked a goal. I'm not happy with the result but I'm happy and confident because playing like this we can do good things this season."

Balotelli started his career at Inter before moving to Manchester City in 2010 and he came off the bench to deafening boos from the home fans shortly after the hour mark. Milan coach Sinisa Mihajlovic was also loudly jeered. He spent two seasons as a player with Inter and was also assistant coach during Roberto Mancini's first spell in charge.

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"We have to go slowly we can't judge Mario after just a bit of a game," Mihajlovic said. "Certainly he did well but he has to continue like this."

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Inter is the only team still with a perfect record after Sassuolo, Palermo and Torino all dropped their first points of the season.

Four of the earlier matches ended with the same 2-2 scoreline. Sassuolo drew at home to Atalanta, in a match that also saw two saved penalties and two red cards, while Torino drew at Hellas Verona.

Newly promoted Carpi picked up its first ever Serie A point at Palermo, while Napoli coach Maurizio Sarri's return to Empoli also ended in a stalemate.

Elsewhere, Alessandro Matri had a dream Lazio debut, scoring a second-half brace to beat Udinese 2-0.

Sampdoria's home match against Bologna was postponed due to bad weather and will be played on Monday.

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Milan started the brighter and new signings Carlos Bacca and Luiz Adriano linked up well, threatening on several occasions. The duo almost put Milan ahead with less than three minutes on the clock as Bacca threaded the ball through to Adriano, but Inter goalkeeper Samir Handanovic came flying out to parry the former Shakhtar Donetsk striker's effort.

They linked up again minutes later, shortly after Stevan Jovetic had fired narrowly past the left post for Inter. However, Adriano blazed over from a tight angle following a great ball from Bacca.

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Milan was playing with a freedom and confidence not seen in its opening two Serie A matches and went close again in the 17th. Giacomo Bonaventura sped down the left flank and sent Adriano clear with a delightful pass but Juan Jesus got back to pull off a perfectly-timed tackle just as the Brazil forward was about to let fly.

It was Inter which went closest in first-half stoppages, when Mauro Icardi sprung the offside trap to run through clear on goal but Diego Lopez pulled off a great save with his legs.

Lopez rescued his side again 10 minutes after the break, finger-tipping Guarin's header over his crossbar.

However, he could do nothing three minutes later when Guarin hit a screamer into the far bottom corner on a counter attack.

Balotelli was brought on in the 61st minute and he almost helped Milan level with his first touch as his free kick flashed across the face of goal but no one could tap it in.

The Italian forward went even closer 12 minutes from time with a long-range effort which smacked off the base of the left upright, while he also tested Handanovic with a free kick from distance which the Inter goalkeeper managed to palm off the line.

Copyright 2015 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

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