Cagliari forward Yael Trepy is in intensive care in hospital, the Italian club said on Monday without giving details on his condition.
According to L'Unione Sarda newspaper, Trepy was involved in an incident in a swimming pool in northern Sardinia.
The 20-year-old player is at the Santissima Annunziata Civil Hospital in Sassari, Cagliari said.
"Everyone at Cagliari Calcio is thinking of Yael and his family," the Serie A team announced in a statement. "The club also asks that their privacy be fully respected and will provide further updates when available."
Trepy, who scored once in his eight Serie A games last season, played in a 1-0 win over Arezzo in the Coppa Italia on Friday.