Napoli s Victor Osimhen receives medical aid during the Serie A soccer match between Inter Milan and Napoli at San Siro Stadium, in Milan, Italy, Sunday, Nov. 21, 2021. AP
Osimhen suffered multiple face fractures following a clash of heads during Napoli's defeat at Inter Milan on Sunday.
The 22-year-old underwent surgery on Tuesday having titanium implants placed in his cheekbone and eye socket.
"The player is doing well and will remain under observation for the next few days," said Napoli in a statement.
The club said Osimhen was "expected to return to action in three months" which would put him out of contention for the Africa Cup of Nations which runs from January 9 to February 6 in Cameroon.
He will also miss a large swathe of the Serie A season.
Napoli top the table in Italy after splashing out 70 million euros to lure the marksman away from French champions Lille. Osimhen has already scored nine times for the club this season.
For Nigeria he has 10 goals from 19 appearances and has been prominent in their World Cup qualifying campaign for Qatar 2022.
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