The Polish football federation said Sunday he will probably need surgery on the injured left knee.
Napoli striker Arkadiusz Milik could be out for several months after suffering a knee injury in Poland's World Cup qualifier win against Denmark.
The Polish football federation said Sunday he will probably need surgery on the injured left knee which suffered anterior cruciate ligament damage during Poland's 3-2 win against Denmark in Warsaw on Saturday.
"Arek Milik has undergone tests on his injured knee, which have shown damage to the anterior cruciate ligament," Kwiatkowski, the federation spokesman, said on Twitter.
"Arek will return to Napoli on Sunday. He is likely to have to undergo surgery and could be out for several months."
Milik, 22, joined Napoli in August from Ajax and has made a huge impact at the Serie A club. And after two rounds of the Champions League for Napoli he is joint top scorer on three goals along with Lionel Messi (Barcelona), Sergio Aguero (Manchester City) and Edinson Cavani (Paris Saint Germain).