Juventus were stunned by 10-man Sampdoria 2-1 at home on Sunday to miss the chance to reclaim an eight-point lead at the top of Serie A.

Both Inter Milan and Roma suffered humiliating away defeat, respectively at the hands of Udinese and Napoli.

Juvetus seemed to enjoy a plain-sailing match as Sebastian Giovinco's early penalty put them ahead before Sampdoria's Gaetano Berardi saw red for two first-half bookings.

But the numerical advantage did little to help the hosts, as Mauro Icardi levelled the scores shortly after the break.

Icardi completed his brace with what proved to be the winner, his sensational strike rattling the Bianconeri to condemn them to a second home defeat of the season, also earning Delio Rossi a first victory as Samp boss.

Juventus head coach Antonio Conte insisted his side is human and could lose games.

"I am not bursting with joy when I lose," Conte said. "I struggle to absorb defeat and we will not look back fondly over this match. We had the advantage and deserved to be in front.

"This is a game that we must reflect on and will help us to grow up. It's part of the maturation process for a young side, let's put it like that.

"It is certainly irritating to lose on counter-attacks and we will analyse what we did wrong today. Juventus are only human, we are not martians," he said.

Delio Rossi gave the credit to his Sampdoria players for beating Juventus.

"I am very happy, above all for the guys, as this was an incredible achievement," said Rossi less than a month after taking over from Ciro Ferrara.

"We won against the champions of Italy while playing with 10 men. I made a tactical adjustment during the half-time break, but the lads were amazing in completing this comeback.

"Perhaps Juve weren't as unstoppable as in previous occasions and it certainly wasn't their best performance," he said.

Juventus now lead the second-placed Lazio by just five points ahead of a daunting trip to Parma.

Roma were thrashed by Napoli 4-1 in a one-sided game where Edison Cavani completed his hat-trick at the 70th minute to put the hosts 3-0 up. Pablo Daniel Osvaldo grabbed one back for Roma three minutes later before Christian Maggio scored Napoli's fourth goal in the 90th minute.

Udinese scored three goals in the second half to beat 10-man Inter 3-0.

Antonio Di Natale was on target twice with Luis Muriel also scoring for Francesco Guidolin's side, who were aided by a red card for Juan Jesus in the 65th minute.

The win lifts Udinese up to eighth in the table, level on points with AC Milan, who have a game in hand, while Inter remain in fourth.

AC Milan further reduced the gap on the top six thanks to a 2-1 win over Siena at the San Siro.

Second-half goals from Bojan Krkic and Giampaolo Pazzini earned the Rossoneri the points with Michele Paolucci scoring a late consolation for the Tuscans, who remain rooted to the foot of the table, six points adrift of safety.

Pescara eased their relegation worries with a stunning upset of Champions League hopefuls Fiorentina 2-0 in Florence.

A last-gasp goal from substitute Amauri condemned his former club Palermo to another defeat, 2-1 at Parma, as the Gialloblu claimed a third consecutive victory.

Isaac Cofie's first goal for Chievo settled a narrow 1-0 victory over Atalanta that keeps the Gialloblu in the hunt for a top-half finish.

Marco Borriello struck a second-half brace to help Genoa down fellow strugglers Bologna 2-0 and claim only their fourth win of the season.