Napoli looked to have done enough to claim all three points at the San Paolo after Gonzalo Higuain ran on to Marek Hamsik's through ball to beat Mattia Perin in the 18th minute.

But Rafael Benitez's men failed to build on their lead and paid the price less than 10 minutes from the end when Genoa won a freekick after a foul by Dries Mertens which earned the Belgian a yellow card.

Calaio was handed the honours and from nearly 30 metres out stepped up to curl the ball over the wall and in off Pepe Reina's post as the Spanish 'keeper looked on in shock.

Instead of reducing the gap to second-placed Roma to four points, Napoli are now six behind Rudi Garcia's men, who themselves are nine behind leaders Juventus albeit with a game in hand.

Fiorentina remain fourth, six points behind Napoli, although La Viola had to thank Mati Fernandez for helping grab a share of the spoils five minutes from the final whistle.

The hosts broke the deadlock through striker Antonio Cassano six minutes from the interval although only two minutes later Juan Cuadrado got on the end of Alessandro Matri's delivery to beat goalkeeper Antonio Mirante to level.

Former Fiorentina flop Amauri restored Parma's lead, in the 51st minute, from the penalty spot after Nenad Tomovic fouled Jonathan Biabiany just as the Frenchman was getting his head to a cross.

The visitors suffered another blow two minutes later when Modibo Diakite, who had been booked just before the half hour for a foul from behind on Cassano, saw red after another foul on the former Inter and AC Milan striker.

Despite being a man down Fiorentina pressed forward looking for an equaliser and when the visitors won a late free kick Fernandez spoiled the Parma party with a superbly-struck curling effort which had Mirante scrambling back into his own net.

Parma brought Raffaele Palladino off the bench and he flashed a header wide of the goal within a minute of coming on.

The match finished level, but on a sour note after a scuffle between Borja Valero and Gianni Munari led to both players being sent off in the fourth minute of added-on time.

On Sunday Carlos Tevez struck his 14th league goal of the campaign to secure a 1-0 derby win over Torino and help Juventus restore their nine-point lead over Roma.

Roma had reduced the gap to six points with a 1-0 win away to Bologna on Saturday.

Adel Taarabt and Adil Rami scored either side of half-time to secure a precious 2-0 win for AC Milan away to 10-man Sampdoria and keep the struggling Serie A giants' resurgence on track.

Milan have now lost only once in the league under Clarence Seedorf and their second win on the trot, following a 3-1 reverse to Napoli two weeks ago, was all the sweeter as city rivals Inter were held to a 1-1 draw by struggling Cagliari at the San Siro which was the 10th draw for both the clubs this season.

Milan are now only five points behind Inter in the first Europa League qualifying spot.