Italy won a scintillating contest to reach the last four and top Group B ahead of the Czech Republic despite twice surrendering the advantage in Mlada Boleslav.
The UEFA European Under-19 Championship's leading scorer, Tomas Necid, fired in his third finals goal to cancel out Andrea Poli's opener before a frenzied second half produced five more strikes.
Jan Moravek provided an instant response to substitute Giacomo Bonaventura's effort before Alberto Paloschi's penalty and Poli's second looked to have ended the contest only for Moravek to set up a frantic finish.
The Azzurrini were reduced to 10-men when the scoreline was at 3-2, with Andrea Mazzarani getting his marching orders for a second bookable offence.
Francesco Rocca's side will now face Hungary in Wednesday's semi-final, while Germany play the hosts in the other tie.
In the process of qualifying, the quartet of semi-finalists, along with the two third-placed sides England and Spain, also booked their places at the FIFA Under-20 World Cup in Egypt next year.
Italy: Fiorillo, Darmian, Formiconi (Tagliani 89), Albertazzi, Bruscagin, Raggio Garibaldi, Mazzarani, Poli, Forestieri (Bonaventura 46), Paloschi (Marchetti 78), Okaka Chuka.
Francesco Rocca (Italy coach):
"The way I saw it, it was a very tough first half and then a more disciplined and together performance by us in the second. Both sides contributed a lot and I have to say I am satisfied. The way you prepare is crucial for these games because all the teams are capable of playing top-class football. So it was our preparation that won us this match in the end. We did a good job. We came into this championship with two goals – to reach the semi-finals and to get to the World Cup. We have achieved both targets. I would like to congratulate the organisers of this tournament because it has been tremendous."
MATCHDAY 3 RESULTS
Sunday July 20
Hungary 1-2 Germany
Spain 4-0 Bulgaria
England 3-0 Greece
Italy 4-3 Czech Republic