In a statement, Napoli said that Kosovo captain Rrahmani had injured a tendon in his left thigh and that he had "begun the recovery process".

Napoli did not say how long centre-back Rrahmani -- an ever-present for coach Luciano Spalletti so far this season -- would be out for but Italian media reported that the 28-year-old would be sidelined for at least three weeks.

That would keep him out for the rest of Napoli's Champions League Group A campaign, which has begun with three straight wins.

Napoli will qualify for the knockout stages with two games to spare on Wednesday should they beat Ajax in Naples.