Dries Mertens will continue to be assessed after Napoli's leading goalscorer suffered an ankle injury.
Mertens netted the opener in a 2-0 win at local rivals Benevento on Sunday to send Maurizio Sarri's side back above Juventus and into top spot in Serie A.
But the Belgium international had to be replaced late in the second half after he was caught by a heavy challenge from Benevento defender Berat Djimsiti, who was booked for the tackle.
In a brief statement released on Monday, Napoli indicated Mertens' injury is not serious but placed no timescale on his recovery.
Dries Mertens has suffered a light Grade I sprain to his left ankle. His fitness will be assessed during training tomorrow #SSCN-- Official SSC Napoli (@en_sscnapoli) February 5, 2018
"Dries Mertens has suffered a light Grade I sprain to his left ankle," Napoli posted on Twitter. "His fitness will be assessed during training tomorrow."
Mertens has hit 14 goals in Serie A this term to help Napoli sit a point clear of champions Juventus at the top of the table.
Napoli are next in Serie A action at home to Lazio on Saturday before taking on RB Leipzig in the Europa League on February 15.