Lazio edged 10-man Roma 2-1 at the Stadio Olimpico to climb to third in the Serie A table and claim a derby double over their rivals this season.
As hosts of this Derby della Capitale, Roma were almost immediately on the back foot after goalkeeper Maarten Stekelenburg was sent off for bringing down Lazio striker Miroslav Klose in the area. Hernanes converted the resulting penalty in the 10th minute.
Roma equalised six minutes later through Fabio Borini but Stefano Mauri put Lazio in front for good shortly after the hour mark to send Roma to their first loss at home since October 23.
Lazio ended the game down to 10 men after Lionel Scaloni was sent off four minutes from time for a second bookable offence.
Lazio leapfrogged Udinese, who drew with Atalanta, into the last Champions League qualifying place.The defeat left Roma 10 points behind Lazio.
Inter Milan battled back from two goals down at home to Catania to salvage a 2-2 draw and ensure they did not suffer a sixth straight defeat in all competitions.
Alejandro Gomez and Mariano Izco put the visitors in control but Diego Forlan and Diego Milito struck to earn Claudio Ranieri's side a tie.
Napoli picked up a controversial three points to close in on the top four with a 2-1 win at Parma.
Edinson Cavani put the visitors in front with a dubious penalty before Cristian Zaccardo grabbed a deserved equaliser in the 77th minute.
Ezequiel Lavezzi then scored a winner from an offside position as the home side were punished for their failure to take their chances while they also had two penalty claims turned down.
Cesena's Serie A future is looking even bleaker after they were beaten 2-0 by Fiorentina to see the gap between themselves and safety increase to nine points.
An own goal by Vangelis Moras and a Matija Nastasic strike earned all three points for Fiorentina, who got a much-needed win to take them six points clear of the relegation zone.
However, the performance by the Viola will have done little to warm the hearts of the Florentine spectators, who will hope for better at Parma on Wednesday when they have the chance to move into the top eight.
Udinese slipped to fourth in Serie A after failing to find a way past Atalanta goalkeeper Andrea Consigli in a 0-0 draw.
Consigli produced a wonderful display to repel the home side's best efforts with Udinese dropping below Lazio as a result. Udinese talisman Antonio Di Natale will have the greatest sense of frustration having come off worse from his personal duel with Consigli.
Giuseppe Sculli's second goal rescued a point as Genoa drew 2-2 after they had slipped behind at Lecce with just nine minutes remaining.
Sculli had opened the scoring in the 21st minute, a lead Genoa held until Luis Muriel levelled just after an hour's play. Davide Brivio thought he had won it for Lecce when he netted in the 81st minute but Sculli was on hand to claim the draw with five minutes to play.
Siena gave their Serie A survival hopes a huge boost with a comprehensive 3-0 victory over fellow strugglers Cagliari.
Erjon Bogdani scored the opener four minutes before half-time and late goals from Emanuele Calaio and Cristiano Del Grosso earned the Bianconeri back-to-back wins for the first time this season after last weekend's 4-1 victory over Palermo
Bologna bounced back from last week's defeat to Udinese with a 1-0 triumph over struggling Novara.
The 3-1 loss to Udinese was Bologna's first defeat of 2012 but they got back on track today thanks to Robert Acquafresca's late winner.
Acquafresca netted in the 82nd minute to help save the blushes of team-mate Marco Di Vaio, who saw his early penalty saved by visiting goalkeeper Samir Ujkani. The victory lifts Bologna six points above the relegation zone but leaves Novara deep in trouble in 19th spot, a massive 12 points adrift of safety.