Paul Onuachu suffered a hamstring injury in Genk's 1-1 draw with Royal Antwrep in Belgium topflight on Sunday.
The development leaves the Nigeria international in doubt for Africa Cup of Nations finals in Cameroon and makes him the second potential loss in Nigeria's attacking role after Victor Osimhen's recent injury concern.
Before suffering the injury, the former Midtylland star had opened scoring for Genk in the first half and was later replaced by Ike Ugbo 20 minutes from full time as the hosts surrended their home lead to late equaliser.
With just three weeks away from the continental showpiece, the 27-year-old is likely to be ruled out of the tournament due to one month timeframe on the sidelines despite Genk is yet to confirm his exact return date.
Commenting on his injury situation, Genk manager Bernd Storck told Belgian newspaper Sporza: "He suffered a muscle tear. I already had the feeling that I had to replace him, but he said he could continue.
"And then he suffered a hamstring injury during a spurt. He will not be able to play for the next three, four weeks."
Onuachu, now, becomes the third player to possibly miss the Afcon, after the avaliablity of Watford midfielder Oghenekaro Etebo and Victor Osimhen still remains a major doubt.
Meanwhile, Interim head coach Austine Eguavoen could announce his provisional list for the competition this week as the Super Eagles will begin their campaign in Cameroon against the Pharaohs of Egypt on January 11.
With Osimhen and Onuachu's injury concerns, in-form Union Berlin striker Taiwo Awoniyi and Emmanuel Dennis of Watford could profit from the situation in the race to make the preliminary squad for the championship.
After showdown with the Pharaohs on January 11, the three-time African champions will continue their Nations Cup Group D campaign in Garoua against Sudan four days later before Guinea-Bissau on 19 January.
