Internazionale slipped to just a second defeat of the season after Juventus won at the Giuseppe Meazza, while Roma continue in pursuit.
Fiorentina maintained their grip on the fourth UEFA Champions League spot, although Milan and Udinese both won.
Reigning champions Inter, whose first Serie A loss of the campaign came at Napoli earlier this month, were beaten 2-1 at home by Juve.
Third-placed Juve took the lead early in the second half through Mauro Camoranesi and made it 2-0 on 63 minutes courtesy of David Trezeguet.
Maniche replied with a late consolation for Inter, who have seen their lead at the summit now whittled down to four points.
Roma played much of the second half with 10 men, but showed admirable fighting qualities to post a 2-1 win at home to struggling Empoli.
Max Tonetto put Roma ahead on 36 minutes, only for Empoli to level five minutes into the second half through Sebastian Giovinco.
Midfielder Simone Perrotta was sent off for the hosts on 57 minutes, but Roma overcame that hindrance to notch the winner through Christian Panucci on 63 minutes.
Fiorentina remain on course to qualify for the UEFA Champions League after a 1-0 home triumph over 10-man Lazio.
The visitors had Massimo Mutarelli sent off for a second bookable offence on 38 minutes and Giampaolo Pazzini grabbed the decisive goal on 77 minutes.
Milan are still four points behind Fiorentina after a battling 1-0 win at Torino.
Brazilian sensation Alexandre Pato scored the only goal of the game when he struck midway through the second half.
Cagliari remain bottom of the table after conceding a late equaliser in a 1-1 draw at Sampdoria, with the result denting the hosts' bid for Champions League football.
Pasquale Foggia put Cagliari in front four minutes before half-time, but Daniele Franceschini rescued a point for Samp in the first minute of stoppage-time.
Udinese leapfrogged Sampdoria in the table after a comfortable 2-0 home success over lowly Livorno.
Fabio Quagliarella opened the scoring after 19 minutes and Antonio Di Natale added the second goal just two minutes after the half-time interval.
Reggina are stuck in the relegation zone after requiring an injury-time goal to secure a 1-1 draw at home to Napoli.
Roberto Sosa broke the deadlock for Napoli on 76 minutes, but Franco Brienza denied the visitors a win with an equaliser two minutes into injury time.
Genoa moved above Palermo in the Serie A table after a 3-2 win away to their Sicilian opponents.
Palermo were in front through the in-demand Amauri's penalty on 24 minutes, but Genoa equalised through Luciano Figueroa six minutes later.
Gaetano De Rosa nosed Genoa ahead five minutes into the second half and Abdoulay Konko made it 3-1 on 61 minutes before Amauri replied with a late consolation in injury time.
Massimo Maccarone struck twice late on against former club Parma to clinch a 2-0 home win for Siena.
The striker, who spent a brief spell on loan at Parma in the 2004/05 season, scored with three minutes to go before converting a penalty deep into injury time.
Catania's battle to stay in Serie A received a minor lift after a creditable 0-0 draw at Atalanta.