- Diego Milito scores the only goal as Inter beat Milan 1-0 in the San Siro derby
- The result opens up the Serie A title race with just six points between the top five
- Juventus and Udinese fail to win but Lazio close gap with 2-0 victory over Atalanta
Diego Milito scored the only goal as Inter beat Milan 1-0 in the San Siro derby, a result that threw open the Italian Serie A title race after the top three teams all failed to win on Sunday.
After leaders Juventus and third-placed Udinese both struggled in earlier matches, defending champions Milan knew victory over their city rivals in the evening kick-off would send them two points clear at the top of the table.
And Milan nearly took the lead on the stroke of halftime when Mark van Bommel's strike crashed against the crossbar with goalkeeper Julio Cesar well beaten.
Inter made the most of that stroke of good fortune and Argentine forward Milito scored the only goal nine minutes after the break.
Milan defender Ignazio Abate slipped as he attempted to clear Javier Zanetti's cross and Milito was on hand to stroke the ball home.
Inter's victory consolidated fifth place, but just six points separate the top five teams after 18 games.
The defeat left Milan a point behind Juventus, who remained top and unbeaten after a 1-1 draw at home to mid-table Cagliari.
A superb team move resulted in striker Mirko Vucinic tapping home the opener for Juve after just seven minutes, but the Sardinian visitors leveled early in the second half through Andrea Cossu's long-range strike.
Udinese dropped two points behind Milan after slipping to a 3-2 defeat at Genoa.
Damiano Ferronetti headed Udinese into the lead but quick-fire goals from Andreas Granqvist and Bosko Jankovic gave Genoa the advantage early in the second half.
Rodrigo Palacio added a third before Antonio Di Natale pulled a goal back from the penalty spot after Genoa captain Marco Rossi had been sent off.
Goals from Brazilian midfielder Hernanes and veteran Germany striker Miroslav Klose gave Lazio a 2-0 home win over Atalanta, putting the Rome club five points behind Juve in fourth position.