Josh Mantellato kicked a 78th minute drop goal after a side largely made up of Australian journeymen and Italian part-timers managed to keep error-prone England scoreless throughout the entire second period of their only World Cup warm-up.
Steve McNamara’s humiliated side face Australia in the tournament opener at Cardiff next Saturday but their preparations were in turmoil after this disaster.
Sam Tomkins (2) and Carl Ablett scored first half tries but Kevin Sinfield could only add one conversion and - though they led 14-12 at the break - the hosts always looked nervy.
St Helens prop Anthony Laffranchi gave Italy an eighth minute lead and they gained so much confidence.
Hooker Dean Parata exposed awful goalline defence for their second after Leeds Rhinos centre Ablett had responded and Mantellato’s second conversion kept them in front.
England briefly rallied amid a thunderstorm but things got worse for them in the second period as they made mistake after mistake to let Italy off the hook.
The visitors - who only arrived here on Wednesday - defended well but, in fairness, were not really troubled by an inept England side who had spent two weeks training in South Africa.
A Ray Nasso penalty in the 70th minute levelled things and after Josh Charnley’s error, Mantellato stepped up.