The Italian international bagged two goals - the first from the penalty spot - to earn his side a key win against a resurgent Roma.
Although Vincenzo Montella grabbed a goal back for Roma, Juve hung on for a victory that keeps them six points clear at the top.
Earlier, Inter had scored in the dying seconds to keep the Serie A title race open with a 1-0 win in a vicious game against Brescia - whilst Milan dropped away from the top two after being stunned by a loss to minnows Empoli at home.
A last-gasp goal from Hernan Crespo may only have briefly put Inter within three points of leaders Juventus, but a draw would have made the task of catching the Bianconeri mountainous.
The game had been marred by three dismissals - two for the visiting Nerazzuri with Cristiano Zanetti sent off for swearing at the referee following a booking in the first half, and being followed for an early shower by team-mate Christian Vieri and Brescia's Fabio Bilica for an incident on 63.
Milan were rocked by a 1-0 home defeat to Empoli - with highly-rated Antonio Di Natale scoring an eighth minute goal for the minnows.
Milan threw everything forward but despite Empoli being reduced to ten men after Francesco Pratali picked up a second yellow card, could not find an equaliser.
Lazio were forced to come from behind to pick up victory over Piacenza - with Simone Inzaghi and Bernardo Corradi earning a 2-1 victory over the relegation strugglers who had opened the scoring through Ciro De Cesare.
Chievo picked up a 2-1 victory over Reggina, with Federico Cossato and Nicola Legrottaglie scoring for the Flying Donkey's either side of a Mozart goal for the visitors.
Modena edged a five-goal thriller against Bologna - with Guiseppe Sculli scoring a brace in a 3-2 win.
Diomansy Kamara had opened the scoring for Modena before a brace from Giuseppe Signori put the visitors in the lead. Nicola Campedelli was sent off in the final minute for Modena.
An Adrian Mutu penalty gave Parma a tight 1-0 victory over Torino, whilst Luigi Pagliuca grabbed the only goal in Perugia's victory over Atalanta.
Finally Udinese earned a 3-2 win against Como, with Marek Jankulovski, Vincenzo Iaquinta and David Pizarro grabbing the goals for the Bianconeri and Fabio Pecchia and Vedin Music scoring for the visitors.
Italian Serie A
Brescia v Internazionale
Chievo Verona v Reggina
Juventus v Roma
Lazio v Piacenza
Milan v Empoli
Modena v Bologna
Parma v Torino
Perugia v Atalanta
Udinese v Como
Click here for updated Serie A table
