Lazio said he was “shocked with pain” after the death of 19-year-old youth midfielder Daniel Guerini.
He was in the Lazio U-19 team and previously played for Turin, Fiorentina and SPAL at youth level.
Lazio said they would “gather around the family” of Guerrini, who joined the Primavera team in Rome in January.
“They are very sad,” said Turin, who made his debut in 2017 after leaving Lazio.
Fiorentina, where Guerini spent two terms as part of his academy, said he was “shocked and saddened”, while SPAL, having spent some time on loan in 2020, said “the football world is in mourning for the sudden death” of the teenager.
Roma, Lazio’s rivals in the city, as well as a number of other Italian clubs, including Inter Milan, Atalanta and AC Milan, also shared their condolences on Twitter.