The Colombia international received treatment after colliding with striker Ignacio Pussetto minutes into the game at the Stadio San Paolo.

The 30-year-old, who is on loan from Arsenal, was treated on the pitch but later returned to play with bandages around his head.

But 41 minutes later, Ospina collapsed to the ground as medics rushed on, with the player stretchered off and transferred to the nearby San Paolo hospital in an ambulance for tests.

"Fortunately it's nothing serious, he's conscious, they did a CAT scan that is negative, he'll remain under observation tonight," said coach Carlo Ancelotti.

Napoli later released a statement saying Ospina had suffered "a hypotensive crisis resulting from a head injury", which is a sudden fall in blood pressure which can cause dizziness and fainting.

"Ospina will be transferred in the next few hours to the Pineta Grande Clinic where he will stay under observation for the next 24 hours," the statement added.

Ospina joined the Italian club last August from Arsenal on a one-year loan with an option to buy.