Northern Ireland's Euro 2012 qualifying campaign has ended with defeat in Pescara.
Nigel Worthington's side had no chance of qualifying for next year's finals and were brushed aside by the 2006 world champions, who had already qualified for Poland and Ukraine.
AC Milan's Antonio Cassano put the home side ahead with a low volley in the 22nd minute before doubling his and Italy's total soon after half-time.
The forward collected Alberto Aquilani's pass before firing low past Maik Taylor from 20 yards.
West Brom defender Gareth McAuley inadvertently chested the ball into his own net to give the Italians a third.
Serbia were expected to finish in second behind the Italians in Group C but suffered a 1-0 defeat in Slovenia, leaving Estonia to grab second and progress to the play-offs.
