Inter Milan won Serie A following a 2-0 defeat of Parma thanks to two goals from Sweden international Zlatan Ibrahimovic.
Needing to better Roma's result against Catania, Inter were under pressure after their title rivals took an early lead while they struggled to break down Parma.
But Ibrahimovic's goal after 62 minutes regained the initiative and his second after 79 minutes made certain of a third straight league title.
Roma conceded a late equaliser as they drew 1-1 in Sicily.
The results condemned Parma to relegation but saved Catania, who had looked like easing the title the way of Roma when they allowed Mirko Vucinic to give the capital side an eighth-minute lead.
But the Sicilians earned the point which preserved their top flight status thanks to an 85th-minute goal from Jorge Martinez.
Empoli followed Parma through the trapdoor despite a 2-1 win over already-relegated Livorno.
Antonio Busce, after 10 minutes, and Luca Saudati, after 55, gave Empoli a two-goal lead before Alessandro Diamanti pulled a goal back seven minutes from time.
Fiorentina claimed the fourth Champions League spot with a 1-0 win at Torino, rendering the 4-1 defeat of Udinese by fifth-placed AC Milan irrelevant.
Two points clear of Milan before kick-off, Fiorentina got the goal they needed to guarantee entry to the Champions League in the 75th minute through Pablo Osvaldo's bicycle kick.
At the San Siro, the home side had actually fallen behind when Giandomenico Mesto put Udinese ahead in the 32nd minute.
Alexandre Pato equalised three minutes into the second half and Filippo Inzaghi put Milan ahead after 59 minutes.
Goals from Cafu (79) and Clarence Seedorf (88) made sure of what was a fruitless win.
Cagliari drew 2-2 at home to Reggina with the visitors twice fighting back from a goal down thanks to Nicola Amoruso. Joaquin Larrivey put Cagliari ahead in the 18th minute before Amoruso levelled for Reggina 10 minutes into the second half. Paolo Bianco restored Cagliari's lead in the 81st minute but former Juventus striker Amoruso levelled again - this time from a penalty - four minutes from time.
Massimo Maccarone scored twice as Siena drew 2-2 with Palermo.
The former Italy Under-21 international opened the scoring after two minutes but Bosko Jankovic levelled in the 24th minute for Palermo, who took the lead six minutes later when Fabrizio Miccoli scored.
But Maccarone had the last word with his 58th minute effort.
Atalanta beat Genoa 2-0 with goals from Sergio Floccari after 32 minutes and Michele Marconi in stoppage time.
Lazio won 2-1 at home to Napoli with goals from Tommaso Rocchi (14) and Fabio Firmani (71) securing victory before Maurizio Domizzi's 82nd-minute consolation for the visitors.
On Saturday, Alessandro Del Piero scored twic for Juventus as they took a point from a six-goal thriller against Sampdoria.
Juve raced into a two-goal lead with Del Piero and David Trezeguet, with a penalty, both moving to 20 goals for the season early on.
But Antonio Cassano and Christian Maggio brought Samp level.
Cassano then missed the second spot-kick of the afternoon on the stroke of half-time before Del Piero converted the third to become the league's top goalscorer in the 65th minute, just after Mohamed Sissoko had been sent off.
Vincenzo Montella then scored his 141st Serie A goal to bring Samp level once again.
Neither side had anything to play for with Sampdoria certain of their place in the UEFA Cup next season and Juventus guaranteed third place in Serie A.
