Coutinho of FC Inter Milan scores the second goal during the Serie A match between FC Internazionale Milano and Cagliari Calcio at Stadio Giuseppe Meazza on November 19, 2011 in Milan, Italy.

Inter Milan won only its third Italian Serie A game of the season when it beat Cagliari 2-1 on Saturday helped by a controversial Thiago Motta goal which left the Sardinians fuming.

Debutante Cagliari coach Davide Ballardini claimed referees gave the benefit of the doubt to the bigger clubs after television replays showed Motta's goal was offside.

Teenager Philippe Coutinho, called into the team at the last minute after playmaker Wesley Sneijder was injured in the warm up, scored Inter's second before Joaquin Larrivey pulled one back for the visitors.

Inter, which started the game in 17th place, has 11 points with Cagliari on 13 having played a game more.

Saturday's other games produced goalless stalemates as AC Milan's run of five successive wins ended at Fiorentina and a negative Lazio held out for a point at Napoli.

Lazio's share of the spoils was enough to take it top of the table with 22 points from 11 games, one ahead of Udinese, which was visiting Parma yesterday, and Milan.

Juventus, the only unbeaten team and three points behind Lazio in fourth place, was hosting Palermo.

Lazio's match was a complete contrast to the corresponding fixture last season when Napoli came from two goals behind to win 4-3 with an Edinson Cavani hat-trick.