Violence marred the lead-up to the final with unconfirmed reports that at least four fans had been taken to hospital with gunshot wounds.

Hard-line 'ultra' fans of Napoli, many of whom threw rocket flares towards the pitch, even ordered the Serie A giants not to play after rumours spread that one of their supporters had been shot.

Following discussions between Napoli captain Marek Hamsik and an 'ultra' leader, the match eventually kicked off 45 minutes later than scheduled.

Fiorentina 'keeper Neto was given the all-clear despite suffering a finger injury last week while Italy striker Giuseppe Rossi made his return on the bench following his recent recovery from a knee injury.

With no designated striker, Fiorentina started, on paper at least, with a disadvantage which became apparent inside the first 16 minutes when Lorenzo Insigne scored twice to give Napoli a 2-0 lead, his first a sublime curling shot which crept inside Neto's far post after Hamsik's superb lay-off.

Fiorentina's defence was almost caught unawares soon after, with Borja Valero clearing Gonzalo Higuain's attempted tap-in from a corner off the line.

Higuain was denied again moments later when he latched on to Insigne's ball only to see his drive inch wide of Neto's far post.

Napoli clearly had the momentum and were rewarded on 16 minutes when Insigne trailed in late to meet a cross from Higuain after his run down the right, the Italian beating Neto with a shot which deflected off Nenad Tomovic.

"He should be going to the World Cup, no problem," said Napoli coach Rafael Benitez when asked about Insigne's selection chances for Brazil.

"It was an incredible game, it seemed easy at the start but then we came under more pressure. Despite being reduced to 10 men our defence held firm and the lads gave 100%."

Fiorentina coach Vincenzo Montella admitted his side had been caught cold.

"We didn't start well at all, in fact we were unrecogniseable," said Montella.

"But I'm happy about how we fought back. We gave a balanced display and overall I'm proud of the players' performance."

- Total control -

Napoli looked to be in total control, but took their eye off the ball to allow Fiorentina to reduce the arrears just before the half hour.

A long ball from midfield was flicked on by forward Josip Ilicic into the path of Juan Vargas, and as the Napoli defence waited for an offside flag that failed to materialise Vargas pounced to beat a static Pepe Reina.

Alberto Aquilani had the ball in the net for Fiorentina on the stroke of half-time after volleying a free kick past Reina, but it was ruled offside.

Montella replaced Manuel Pasqual with Matias Fernandez shortly after the restart while Benitez added firepower with Dries Mertens replacing Hamsik.

Mertens should have done better with Insigne's cutback on 69 minutes but saw his attempt blocked.

Moments later a tiring Higuain came off in favour of Goran Pandev and, after Fernandez tested Reina with a drive which the keeper tipped over, Rossi replaced Joaquin.

Pandev should have extended Napoli's lead moments later when he ran on to a through ball but Neto came out to block in timely fashion.

Fiorentina were given a boost with a little over 10 minutes to play when midfielder Gokhan Inler saw red after being cautioned for a second time for a foul on behind on Ilicic.

La Viola should have made advantage count but with five minutes left to play Ilicic's attempted chip over the onrushing Reina was wide of the keeper's post.

Fiorentina laid seige to Napoli's goal, but in injury time Mertens finished off a great Napoli counter to seal their fifth Cup and second since 2012.