Joshua Kimmich opened the scoring from inside the penalty area for Germany after 10 minutes, before Ilkay Gundogan added the second goal from the penalty spot at the end of the first half.
Thomas Muller made it 3-0 five minutes into the second half, before two goals in less than two minutes from Timo Werner – the second goal came after a mistake in the Italian defense – made the match elusive for Italy.
Wilfried Gonto pulled the way back from close range when a Manuel Neuer save – the 18-year-old’s first goal for Italy – was pushed into his path, while Alessandro Bastoni’s header close to the post from a corner proved to be a late consolation goal.
The result means that Flick has not suffered any defeat after 13 matches, as his team achieved their first historic victory over Italy in their eleventh meeting.
“We are angry, there are no excuses tonight,” goalkeeper Gianluigi Donnarumma said.
“We have to look each other in the eye and start over to show that this is not the real Italy. We were lacking in everything tonight.”
It was also a forgettable night for England, Italy’s opponents in the Euro 2020 final last year, after their 4-0 defeat to Hungary at Molino – Hungary’s first away win over England since 1953.
Although the Three Lions dominated the early stages of the match, Hungary took the lead when Roland Salai scored from a free kick inside the penalty area.
Reece James headed home from the goal line to prevent Hungary from scoring another goal later in the first half, but Sly stunned the hosts again in the 70th minute when he scored his second goal.
Things went from bad to worse for England as third-place Ádám Nagy crushed Hungary, John Stones was sent off for a second yellow card and Dániel Gazdag completed the defeat.
This defeat is England’s second defeat in a row against Hungary and the fourth match without a victory in the Nations League this season.
“I picked a very small team and that’s my responsibility,” said coach Gareth Southgate.
“I didn’t get the right balance in the two games against Hungary. After the first goal, the anxiety crept in a bit and we couldn’t recover from that.”
The next round of Group A3 matches takes place on September 23, with Italy hosting England and Germany hosting Hungary.
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