Daniel Guerini was killed in a car accident at 19 in Rome on Wednesday evening.
Lazio confirmed the news and the club is in mourning following the tragic death of their 19-year-old youth team player.
Guerini and two other teenage friends were in the car when it collided with a Mercedes Class A driven by a 68-year-old man.
He was born in Rome, and played for Italy at the Under-15 and Under-16 stages.
But Guerini had previously played for Torino, Fiorentina, and SPAL.
The teenager had just turned 19 on Sunday.