Italy coach Roberto Mancini admitted he had feared another goalless draw after his side's 1-0 friendly win against USA in Belgium.
Mancini named a new-look side as he continues to experiment with his options and they were indebted to late substitute Matteo Politano's stoppage-time goal.
The Inter Milan winger, on loan from Sassuolo, struck in the fourth minute of added time after stepping off the bench in the 87th minute.
"We should have scored earlier," Mancini told a press conference. "It looked like it was going to finish 0-0 once again, but this result was more than deserved.
"At times we found ourselves quite stretched as a result of wanting to attack in numbers, but this is OK."
Italy, who failed to qualify for Russia 2018 after drawing the second leg of their play-off against Sweden 0-0, had been held to a goalless stalemate against Portugal in their final Nations League game at the weekend.
The Azzurri have won only three of their last 11 matches and Politano's last-gasp winner was their fourth goal in six, but Mancini is pleased with his side's progress.
"Everybody played very well," he added. "We are where we want to be and are maybe even doing better than expected.
"We're playing well, but need to pick up results when we start playing the European Championship qualifying games."
USA interim coach Dave Sarachan said he expected his side's defeat in Genk to have been his final match in charge.
Goalkeeper Ethan Horvath made a string of fine saves to keep Italy at bay, but the USA had proved to be a tougher nut to crack than they had been in last week's 3-0 defeat to England at Wembley.
"Well, it was my last game," Sarachan was quoted in the Washington Post. "I haven't been told that, but it's evident there's going to be a change in the very near future."
Sarachan named nine players in his starting line-up who were 23 or younger, with the average age of his side 22 years and 71 days.
"To look back on the games that we played, the players that we've exposed to this level, that we brought forth, I'm certain it's going to pay dividends down the line," Sarachan added.
"So, for me, I feel as though when the next person comes in, they're going to have a great starting point and that makes me feel good."