Gonzalo Higuain's hat-trick helped Napoli tighten their grip on the last Champions League place with a 4-2 home victory over 10-man Lazio.
The Argentina striker plundered his first treble for the Stadio San Paolo outfit, while Dries Mertens' wonder goal before half-time made life especially difficult for eighth-placed Lazio.
Edy Reja's men had opened the scoring through Senad Lulic but lost control of proceedings when Albanian defender Lorik Cana saw red shortly after the break.
Ogenyi Onazi did pull one back for the Biancocelesti, who are now five points off Inter and the last European berth on offer in Serie A, before Higuain completed his hat-trick with deft finish deep into stoppage time.
Fiorentina emerged victorious from a 5-3 thriller at Hellas Verona that saw the Tuscans remain the clear favourites to take the first Europa League berth.
Jacopo Sala gave Verona the upper hand early on but Juan Cuadrado and Alberto Aquilani completed a quick turnaround for Fiorentina before half-time.
Borja Valero extended the visitors' lead before Marco Donadel's dismissal allowed La Viola to assert their dominance.
Luca Toni and Alessandro Matri exchanged penalties at the Stadio Marc'Antonio Bentegodi, but Aquilani's late second goal rendered Juan Iturbe's stoppage-time strike a mere consolation.
Samir Handanovic helped Inter survive a first-half onslaught from 10-man Sampdoria before the Nerazzurri hit their straps to plunder a 4-0 victory at the Stadio Luigi Ferraris.
Mauro Icardi opened the scoring for Inter but goalkeeper Handanovic saved Maxi Lopez's penalty and dexterously repelled countless Samp efforts to steer the visitors towards half-time unscathed.
Eder's early dismissal ultimately proved critical to Samp's chances of pulling off a comeback and Inter took advantage of their extra body to wrap up the victory through further goals from Icardi, Walter Samuel and Rodrigo Palacio.
Riccardo Montolivo fired Milan back into the top half of the table and into the race for Europe as they recorded a 1-0 victory over relegation-threatened Catania.
The 18-time Italian champions have spent most of the season in the doldrums but four straight wins have now seen Clarence Seedorf's men close to within five points of city rivals Inter.
Parma's pursuit of European football stalled on Sunday as they had to settle for a 1-1 draw at struggling Bologna.
Raffaele Palladino secured the point with a 79th-minute equaliser for Roberto Donadoni's side, who had trailed to Nicolo Cherubin's strike just before half-time.
Elsewhere, two goals in a minute kept Torino's dreams alive of qualifying for Europe next season as they came from behind to beat Genoa 2-1 in a dramatic finale at the Stadio Olimpico.
Alberto Paloschi netted a hat-trick as Chievo gave their survival hopes a big boost on Sunday afternoon with a 4-2 win at Livorno.