Ghana striker Majeed Waris is facing a battle to be fit for his team's World Cup opener against the USA on June 16.
The 22-year-old picked up a knee injury on Monday during his country's 4-0 friendly win over South Korea.
The Black Stars must call up a replacement for Waris by June 15 if he fails to recover.
Waris has scored four goals in nine games for Ghana since he made his debut in 2012.