Italy's Under-21 side fought back from 2-0 down to earn a thrilling draw in Germany with Fabio Borini's strike.
The Azzurrini faced their first friendly test away from home since Coach Ciro Ferrara took over, following up last week's 3-1 win over Sweden.
It was a rough start in Kassel, as Holtby flashed a shot just over in the opening three minutes.
The same player broke the deadlock by taking advantage of a terrible backpass from 18-year-old Inter midfielder Lorenzo Crisetig.
Mlapa also threatened, but Italy finally got into gear after 27 minutes. Federico Macheda's smart backheel flick freed up Diego Fabbrini, who tried to roll it across for the tap-in, but Rausch made a crucial interception.
Fabbrini had another strike smothered by the German goalkeeper, while at the other end Daniele Mori flung himself at Mlapa to block his solo run from point-blank range.
Italy stepped up the pace before half-time. Alberto Paloschi knocked down a Fabbrini pass for Macheda, whose shot went over the bar.
Moments later Crisetig skipped past two tackles to send Macheda sprinting towards goal, but the Sampdoria striker's first touch let him down and goalkeeper Trapp was able to smother at his feet.
The second half started with a bang with chances at both ends of the field. Juventus youngster Carlo Pinsoglio needed two fantastic saves to keep out Holtby, both times sent clear into the box by substitute Vukcevic.
German goalkeeper Trapp was also called into action when Macheda's through ball released Paloschi.
The home side doubled their lead just shy of the hour mark and it was another error from the Azzurrini, who left Holtby totally unmarked to get on the end of a free kick.
Pinsoglio again came to the rescue to block Didavi running on to a Sukuta-Pasu assist, then Swansea City striker Fabio Borini ran halfway up the pitch before firing over the bar.
Ferrara made an inspired substitution, as Cittadella starlet Manolo Gabbiadini scored within 60 seconds of coming off the bench. He trapped a Riccardo Saponara pass on the edge of the box and flicked an angled drive across Trapp.
Moments later the German goalkeeper had to rush off his line to close Borini and it was the Chelsea-owned forward who equalised, leaping above the crowd to nod in a corner.
Italy still weren't satisfied at wiping out a 2-0 deficit in eight minutes and pushed for the victory, as Trapp parried Gabbiadini's strike.
Germany 2-2 Italy
Scorers: Holtby 14, 59 (G), Gabbiadini 76 (I), Borini 84 (I)
Germany Under-21: Trapp; Jung, Kirchhoff, Neumann, Rausch; Rudy (Didavi 50), Gundogan (Ostrzolek 84), Vogt (Hornschumm 72); Holtby (Schindler 71), Lasogga (Sakuta-Pasu 62), Mlapa (Vukcevic 46)
Italy Under-21: Pinsoglio; Faraoni (Donati 75), Mori, Caldirola, Crescenzi; D'Alessandro (Saponara 60), Marrone (Soriano 91), Crisetig (Romizi 46), Fabbrini (Misuraca 46); Paloschi (Borini 60), Macheda (Gabbiadini 75)
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