Serie A leaders Inter Milan went nine points clear on Saturday after celebrating their centenary with a regulation 2-0 win over second-from-bottom Reggina.

AS Roma can cut the gap back to six points on Sunday if they win at Napoli, where champions Inter suffered their first defeat of the league season last weekend, going down 1-0.

Inter striker Zlatan Ibrahimovic, returning after two weeks out with a knee problem, opened the scoring with a penalty and proved his fitness ahead of Tuesday's Champions League last 16 second leg at home to Liverpool, who lead 2-0.

The Swede, who also hit the bar with a free kick, netted his 15th of the campaign on 14 minutes after Esteban Cambiasso was sandwiched by Carlos Adrian Valdez and Luca Tognozzi.

However, the first contact was just outside the area in the latest of a series of fortunate decisions for Inter this season.

Defender Nicolas Burdisso made it 2-0 on 34 minutes with a bullet header from Luis Jimenez's deep free kick.

Reggina had chances but keeper Julio Cesar, who made a rare blunder for Napoli's goal last Sunday, was back to his best.

"It was important to react after a period that's not been all that positive," coach Roberto Mancini told reporters before turning his thoughts to Liverpool. "It will have to be a special night."

Inter were formed on March 9, 1908 when a group broke away from Milan Cricket and Football Club, later to become AC Milan, because they wanted to open up a team to foreigners. Inter have never been relegated from the top flight since.

Events have been going on all week to celebrate the centenary but the game did not go entirely to plan with Hernan Crespo [Images] hurting his head and joining a lengthy injury list.

Marco Materazzi partnered usual right back Burdisso in central defence with Walter Samuel and Ivan Cordoba out for the season, but Materazzi is suspended for Tuesday so Inter are hoping Cristian Chivu can shrug off a shoulder problem to play.

Captain Javier Zanetti, predominantly a right midfielder nowadays, started at left back with Maxwell injured.

During the party after the game, the San Siro's giant screens showed video messages from former Inter players while a wedding for two fans was also held.

Club president Massimo Moratti, who upset Milan and Juventus during the week with comments about Inter's superiority, also attempted to sing but hastily gave up.

In Saturday's other match, Palermo in eighth drew 1-1 with sixth-placed Udinese after Fabio Simplicio's 20-metre volley for the Sicilians was cancelled out by Felipe's second-half goal.

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