Italy kept alive their hopes of qualifying for the quarter-finals of the World Cup with a bonus-point victory over the United States in Nelson.
The Azzurri scored four tries to one in a scrappy encounter, but while their set-piece looked formidable, they made hard work of the win.
Italy are now level with Australia in Pool C with 10 points, three points behind Ireland.
And if Italy beat Ireland on Sunday in Dunedin and the Wallabies beat Russia, Ireland will be eliminated.
Both sides had strong support in New Zealand's Italian heartland of Nelson but it was the Azzurri who made the stronger start at a blustery Trafalgar Park.
Italy skipper Sergio Parisse went over for a try after only three minutes, the Stade Francais number eight lurking on the shoulder of Quintin Geldenhuys and touching down under the posts.
Italy very nearly scored a second try five minutes later, but despite a fabulous one-handed effort, right wing Tommaso Benvenuti was unable to get downward pressure on the ball after a cute through-kick by full-back Luke McLean.
With Leicester prop Martin Castrogiovanni getting the better of the vastly experienced Mike MacDonald in the early scrums and Saracens full-back Chris Wyles struggling under the high ball in a swirling wind, the United States failed to make an impression in the first 15 minutes.
However, the Eagles, eschewing a kicking game, levelled the scores after 18 minutes when outside-centre Paul Emerick straightened an attack, went blasting through Italy's midfield and put Wyles in next to the posts with a deft pass out of the back of the hand.
Italy regained the lead shortly after courtesy of a Mirco Bergamasco penalty - the result of another collapsed scrum - but the United States came surging back, with MacDonald going on a barrelling run through the heart of the Italian defence and Wyles knocking over a simple penalty after Italy went off-side at the scrum.
However, the pendulum soon swung back in Italy's direction again, fly-half Luciano Orquera ghosting through a gaping hole in the American defence after Parisse, who was his usual classy self, spurned a very makeable penalty and opted for a kick to the corner instead.
With Italy hunting for that valuable bonus point, Parisse again opted for a kick to the corner and this time Castrogiovanni very nearly took advantage, but under pressure from the Eagles' irrepressible captain Todd Clever, he grounded the ball short of the line.
However, despite some fevered defence from the United States, man-of-the-match Castrogiovanni did manage to score just before the break, smashing over from five metres out to make it 20-10 to the Azzurri at half-time.
The United States began the second half in determined fashion but were hamstrung by repeated infringements at the breakdown. Meanwhile, while Italy continued to savage the opposition scrum, they were guilty of too many unforced errors.
But when United States blind-side Louis Stanfill was sin-binned for going off-side at the scrum a sustained period of pressure followed and Italy were eventually awarded a penalty try for collapsing, a score that secured the bonus point.
While his side remain alive in the tournament, Italy head coach Nick Mallett will know they can ill afford to make so many mistakes against a firing Irish outfit.
Eddie O'Sullivan's United States team will finish Pool C in fourth place on four points if the Wallabies, as expected, beat Russia in Nelson.
Italy: Masi, Benvenuti, Canale, Garcia, M. Bergamasco, Orquera, Semenzato, Perugini, Ghiraldini, Castrogiovanni, Geldenhuys, Van Zyl, Zanni, M. Bergamasco, Parisse.
Replacements: Derbyshire for M. Bergamasco (70), Bocchino for Orquera (67), Gori for Semenzato (67), Lo Cicero for Perugini (51), Ongaro for Ghiraldini (73). Not used: Bortolami, McLean.
USA: Wyles, Ngwenya, Emerick, A. Suniula, Paterson, R. Suniula, Petri, MacDonald, Biller, Moeakiola, van der Giessen, Smith, Stanfill, Clever, Johnson.
Replacements: Scully for A. Suniula (46), Malifa for R. Suniula (72), Usasz for Petri (63), Thiel for Biller (29), Pittman for Moeakiola (56), LaValla for Johnson (68). Not used: Danahy.
Sin Bin: Stanfill (59).