MILAN - Inter Milan's Serie A title hopes suffered a new setback as it conceded a stoppage-time equalizer and was held 1-1 at home by relegation threatened Carpi Sunday, while leader Napoli swept to a 4-2 win at Sampdoria.
Rodrigo Palacio gave Inter a first-half lead but Kevin Lasagna stunned the San Siro after the lowly visitors had been reduced to 10 men.
Inter, which has taken one point from its last three home games, took a scarely-deserved lead when Palacio turned in Ivan Perisic's deflected shot six minutes before halftime.
In a dramatic finale, Lorenzo Pasciuti was sent off for a second bookable offence, Carpi goalkeeper Vid Belec denied Palacio and Felipe Melo with a double save before Lasagna broke clear of the Inter defense and drove his shot past Samir Handanovic.
Napoli had no such trouble after Sampdoria midfielder Edgar Barreto unwittingly helped them to an early two-goal lead.
The visitors went ahead in the ninth minute when Gonzalo Higuain intercepted Barreto's wayward back pass to score and Lorenzo Insigne added the second from a penalty in the 18th minute after Barreto had fouled Raul Albiol in the area.
Joaquin Correa swept home Carlos Carbonero's pass to pull one back for Samp on the stroke of halftime but their hopes of a fight back ended when Mattia Cassan was given a second yellow card for hacking down Insigne in the 59th minute.
Within one minute Hamsik added the third when he wriggled between two defenders and poked the ball past Emiliano Viviano.
Eder headed one back, only for Dries Mertens to race past two defenders on the left and fire the fourth for Napoli.
Napoli has 47 points from 21 games, five ahead of Juventus which was at home to AS Roma in the evening game. Inter and Fiorentina are level in third on 41.
A majestic Josip Ilicic set Fiorentina on the way to a 2-0 win over Torino as it bounced back after losing their last two games.
Lazio scored four times in the final half hour as it came from behind to beat Chievo 4-1.
Bostjan Cesar gave the visitors a fifth minute lead but the match turned after he was sent off early in the second.
Antonio Candreva scored twice for Lazio, including the equalizer from a penalty, while Danilo Cataldi and Balde Keita shared the others. In between, Lazio had Stefan Radu sent off and Alberto Paloschi missed a penalty for Chievo.
Palermo hammered Udinese 4-1 in a meeting of two teams who are just above the drop zone and second-half goals by Emanuele Giaccherini and Sergio Floccari gave Roberto Donadoni's Bologna a 2-0 win at Sassuolo.
Bottom club Verona remained winless after drawing 1-1 at home to Genoa.