The Arsenal goalkeeper David Ospina was taken off on a stretcher after collapsing during Napoli’s Serie A match against Udinese on Sunday.
The Colombian, on a season-long loan at Napoli, suffered the initial head injury when he collided with Ignacio Pussetto early in the match.
He then fell to the ground shortly before the break after Udinese levelled at 2-2 having been 2-0 down.
The 30-year-old received treatment before he was brought off the field.
Ospina signed for the Gunners in July 2014 but has only made 27 league appearances for the Premier League side.
He joined Napoli on a season-long loan deal in August 2018.