Antonio di Natale scored twice in injury-time to complete a hat-trick and end the recent good form of Serie A rivals Napoli.

Di Natale punished his hometown club, who had goalscorer Christian Maggio sent off just before half-time, to give the Bianconeri a first win in eight Serie A contests.

It provided Gianni De Biasi with a first victory since he took charge on December 22, easing the club's relegation fears and enabling them to put behind them the misery of the midweek Coppa Italia semi-final defeat to Roma.

Little went right for the visitors at the Stadio Friuli and this was a rare setback for a side who have been galvanised by Walter Mazzarri in recent weeks.

The home side started well and their early initiative was rewarded in the seventh minute when they were awarded a penalty, after Maggio was penalised for holding Ghanaian midfielder Kwadwo Asamoah.

Di Natale took the penalty and although Napoli goalkeeper Morgan De Sanctis parried the effort, the striker was quick to convert the rebound - the first goal Napoli have conceded since December 12.

The Champions League hopefuls were level in the 21st minute, after Marek Hamsik's through-ball fell into the path of German Denis.

Samir Handanovic parried the Argentinian's well-struck right-footed shot but Maggio reacted sharply, following up to score and atone for giving away the penalty.

A minute before the interval Fabio Quagliarella headed Denis' cross against the Udinese crossbar - but that was not the end of the first-half drama.

Maggio, who had already been booked for his involvement in the penalty incident, then picked up a second yellow card for simulation and the visitors were reduced to 10 men for the remainder of the contest.

Quagliarella's 57th-minute effort against his former side was the pick of the chances in an even second half - until the fascinating climax to this contest.

Michele Pazienza's long distance right-footed shot hit the base of the post for the visitors with just a minute of normal time remaining.

Then, in the first minute of injury-time, Di Natale seized on a poor clearance by Pazienza and coolly beat De Sanctis to put Udinese 2-1 ahead.

And two minutes later the striker made the points safe when he advanced on the counter-attack and completed his treble.

Napoli had the final chance of the game - but their afternoon was summed up in the fourth minute of time added on.

Udinese goalkeeper Handanovic impressively tipped over a close-range shot from Quagliarella - and the Partenopei's impressive recent run, which had carried them up to fourth in the table, was over.

The result means the visitors miss the chance to close on the top three, while Udinese climb out of the relegation zone and up to 15th - with a game in hand on most of the teams around them.