Milan won bragging rights in their derby with Internazionale thanks to Kaka's goal.
Mercurial Brazilian Kaka was Milan's derby day hero as his second half strike helped them to a 1-0 win over Internazionale.The game had looked likely to end in a bore draw but after Kaka deflected home Gennaro Gattuso's strike from the edge of the box, Milan ended their neighbour's 40-match unbeaten run.
Milan now edge level on points with Serie A leaders Juventus but showed none of the swagger displayed at Old Trafford, in a game that will not live long in the memory.
Juan Sebastian Veron had the only chance of the first half when his volley was parried by Dida in the Milan goal, while after the interval, the same player arguably squandered Inter's best opportunity when firing a snap-shot over.
Juventus had earlier reopened a three-point lead at the top of Serie A following a convincing 3-0 home win over Siena.
The Bianconeri have seen their commanding advantage at the top of the table whittled away completely in recent weeks by Milan who will move back level if they prevail in the derby with Internazionale later on Sunday.
Alessandro Del Piero was the hero for Juve, notching in either half to set up a comfortable victory.
Del Piero's goals (35 and 63 penalty) sandwiched an effort from Brazilian midfielder Emerson five minutes after the break as Fabio Capello's men eased to all three points.
Palermo maintained their European aspirations with a fine 2-0 success against Roma, Franco Brienza and Luca Toni grabbed the goals for the hosts who now move four points clear of their rivals.
Cagliari could only manage a point from their home clash with basement boys Atalanta after squandering the lead on three separate occasions.
Luigi Sala cancelled out Antonio Langella's early effort and Stephen Makinwa then responded when Mauro Esposito had restored the Sardinians' lead.
Nelson Abeijon appeared to have won it for Cagliari, but Michele Marcolini kept his nerve to convert a last-minute penalty and earn the visitors a share of the spoils.
Reggina edged past Chievo courtesy of a Shinsuke Nakamura strike five minutes before half time, while Lecce saw off Messina by the same scoreline with a late Sasa Bjelanovic effort.
Lazio increased Parma's relegation worries with a 2-0 triumph at Stadio Olimpico; Massimo Oddo put the hosts ahead with a 19th minute penalty and Antonio Filippini sealed the win with a last-gasp second.
Bologna and Livorno shared the points after a goalless draw.
Match summaries:
Bologna 0-0 Livorno
Cagliari 3-3 Atalanta
Internazionale 0-1 Milan
Juventus 3-0 Siena
Lazio 2-0 Parma
Lecce 1-0 Messina
Palermo 2-0 Roma
Reggina 1-0 Chievo
