The American-born striker fired home a stunning long-range equaliser just 60 seconds after coming on as a 57th-minute substitute and confirmed Italy's triumph with another goal in stoppage time.
Midfielder Daniel de Rossi banished bitter memories of his last encounter against the Americans with a spectacular shot in the 72nd minute as the Italians swamped their 10-man opponents in the second half.
The Americans had taken the lead just before the interval through a Landon Donovan penalty but were fighting a rearguard action after midfielder Ricardo Clark was sent off in the 33rd minute.
Rossi, who left New Jersey aged 12 to play for Parma, made an immediate impact when he won the ball in midfield before unleashing a swerving shot past American goalkeeper Tim Howard.
De Rossi's shot 15 minutes later came from even further out and again gave Howard little chance.
He celebrated with an elaborate dive into his own dug-out, in stark contrast to the ugly scenes when he received a four-match ban at the last World Cup in 2006 for elbowing American strike Brian McBride.
"That was a pretty bad blow but this time was lot different," De Rossi told reporters.
Rossi struck again four minutes into stoppage time after Andrea Pirlo dragged the ball back into his path.
American coach Bob Bradley was asked how he felt about conceding two goals to a player born in the U.S.
"I have known him since he was 10 years old," he said. "We had hoped he would play for us. He is a very talented young player and today is a very exciting day for him and a very disappointing one for us."
RIDING ROUGHSHOD
The Italians, wearing a replica of their 1934 World Cup- winning kit with sky blue tops and burgundy shorts and stockings, rode roughshod over their tiring opponents in the second half.
Tall striker Vincenzo Iaquinta was guilty of several misses and substitute Luca Toni wasted a golden opportunity three minutes from time.
The Americans scuffed two excellent first-half chances, both set up by the pace of Donovan. The first Michael Bradley tamely hit at Italy goalkeeper Gianluigi Buffon and the second was missed by Jozi Altidore.
Altidore did win a penalty in the 41st minute after being tugged to the ground by Giorgio Chiellini. Donovan sent Buffon the wrong way as the Americans sought their first win over Italy in 10 attempts.
Clark's red card came after a lunging tackle on Gennaro Gattuso in the 33rd minute, although it seemed a harsh decision by Chilean referee Pablo Pozo.
Italy next play Egypt and the U.S. face Brazil on Thursday.
