Napoli announce goalkeeper Alex Meret has fractured bones in his vertebrae and has been released by the Italy squad.
He had been called up for international duty ahead of the three World Cup qualifiers against Bulgaria, Switzerland and Lithuania.
However, the tests at the Coverciano medical centre showed a knock he sustained during the 2-1 win over Genoa was far worse than previously thought.
A statement confirmed Meret has suffered a fracture of the left transverse apophysis of the third and fourth lumbar vertebrae.
The injury could rule Meret out for several weeks and is rather unusual in sportsmen, probably caused by a collision.
Usually, this type of injury is found after a high-impact trauma, such as a car accident.