Internazionale failed to win in Serie A for the first time in nine matches when they were held to a 0-0 draw at Udinese yesterday.
The unbeaten champions had Brazilian winger Cesar sent off for two quick bookings after just 21 minutes but still had the better chances to beat fifth-placed Udinese with Julio Cruz and strike partner Zlatan Ibrahimovic going close.
Inter's lead from last week has been cut to five from seven points after second-placed Roma won 1-0 at home to Palermo on Saturday. Juventus, 13 points behind Inter in third, were scheduled to visit Livorno in the late game.
Brazilian striker Pato scored twice to give Milan a 2-0 win over 10-man Genoa and lift them to seventh. The 18-year-old has now scored three in his first four games for the club and three in two at the San Siro where Milan had failed to win against Italian opposition before his arrival at the start of the month.
Fourth-placed Fiorentina moved level on points with Juventus after Adrian Mutu's 13th league goal of the season set up a 2-0 victory at Empoli.Reuse content