Napoli will likely have to make do without the services of Arek Milik for several months amid reports the Poland international suffered a torn ACL in Saturday's 3-2 World Cup qualification win over Denmark.
The prolific striker won the penalty that allowed Robert Lewandowski to make it 2-0, but was forced to stay behind in the dressing room at half-time due to a knee injury.
Milik underwent a series of tests after the final whistle and Poland's media officer Jakub Kwiatkowski has revealed he has damaged his ACL.
"Arek Milik has undergone tests on his injured knee, which have shown damage to the anterior cruciate ligament," Kwiatkowski posted on Twitter.
"Arek will return to Napoli on Sunday. He is likely to have to undergo surgery and could be out for several months."
Napoli have yet to confirm the extent of the injury, but Milik appears to be set for a lengthy spell on the sidelines following Kwiatkowski's statement.
The 22-year-old joined Napoli from Ajax for a transfer fee of EUR32 million during the close-season and impressed in the opening stages of the 2016-17 campaign, scoring seven goals in nine appearances in all competitions for the Stadio San Paolo side.