Umar Sadiq, a striker for the Super Eagles, suffered an injury during Real Sociedad's Sunday loss to Getafe on the road.
Sadiq's most recent injury makes him questionable for the Super Eagles' international friendly against Algeria on September 27 in Oran.
The Nigerian international, who joined La Real this summer, has contributed significantly to the team in each of the three games in which he has played.
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On his debut, the tall striker scored against Atletico Madrid to give Sociedad a draw against the dominant Spanish team.
He also starred in their 1-0 victory over Manchester United at Old Trafford in the UEFA Europa League.
The former Almeria striker started the game against Getafe, but could only last 37 minutes on the pitch of play as he got replaced by Mohammed Ali Cho.
On the club’s Twitter handle on Monday, the club wished him well as he recovers from the knock with tests to be carried out to determine how long the Nigerian international will be out of action.
“We are with you, Sadiq,” the club said through their Twitter handle.