Brighton winger Zadok Yohanna will miss the second leg of Nigeria's 2027 Africa U-23 Cup of Nations second qualifying round tie against the Democratic Republic of Congo.
Zadok limped off the pitch in the first leg at the TP Mazembe Stadium, Lubumbashi, due to injury.
The 19-year-old has returned to England for further assessment and treatment.
The Olympic Eagles will have to overturn a 2-0 deficit from the first leg for them to progress into the final qualifying round.
Sierra Leone or Burkina awaits the winner of the two-legged encounter.
Egypt will host the 2027 U-23 AFCON, which will serve as a qualifying tournament for the 2028 Los Angeles Olympics.
2027 U-23 AFCONQ: Zadok ruled out of Olympic Eagles rematch against DR Congo