Claudio Marchisio netted a late winner as Juventus moved three points clear at the top of Serie A with a 2-1 victory at Siena.
Andre Pirlo opened the scoring for Juve in the 14th minute with a superb free-kick, but Siena drew level in the 47th minute when Emanuele Calaio headed home Angelo's cross.
Marchisio had the last word as he fired in a superb volley from the edge of the area to extend Juve's unbeaten streak to 47 games.
In the evening derby match, 10-man Inter Milan held off rivals AC Milan to secure a landmark 1-0 win at the San Siro.
Inter paved the way for their 50th Milan derby triumph when Walter Samuel headed home in the fourth minute after Christian Abbiati failed to claim the ball.
Yuto Nagatomo's dismissal after the break for a second bookable offence heaped pressure on Inter and they were fortunate to avoid a late penalty when Samuel appeared to bring down Robinho in the box.
Lazio kept themselves in touch with the pace-setters after Miroslav Klose bagged a double in a 3-0 win over Pescara.
Brazilian midfielder Hernanes gave Lazio a fifth minute lead when he sent a curling free-kick past the helpless Mattia Perin.
Klose doubled their advantage in the 25th minute with a cool finish after latching onto Andrea Candreva's through ball, while he headed home his fifth league goal of the season 10 minutes later.
Elsewhere, Nene netted the only goal as Cagliari moved off the bottom following an upset 1-0 win over Torino and Catania maintained their solid start with a 2-0 win at home to struggling Parma.
Fiorentina spurned a number of chances but still claimed a precious 1-0 home win over Bologna and Michael Bradley was on target in Roma's 2-0 defeat of Atalanta.