Midfielder Wilfred Ndidi has had to withdraw from Nigeria’s squad for the Africa Cup of Nations through injury and been replaced by Belgian-based Alhassan Yusuf, the Nigerian Football Federation said.

Ndidi, 27, was injured in his club’s 2-0 win at Cardiff City on Dec. 29, although details of the injury were not made clear by either his club or Nigeria.

Leicester teammate Kelechi Iheanacho is also struggling with injury but was still being assessed at Nigeria’s training camp in Abu Dhabi, the federation added in a statement.

Iheanacho, also 27, had missed the last two matches for his club, who are runaway leaders in the Championship in England.

The 23-year-old Yusuf is uncapped but helped Royal Antwerp to the Belgian league title last season and competed in all their Champions League group matches between September and December.

Nigeria open their Cup of Nations campaign on Jan. 14 with a Group A game against Equatorial Guinea in Abidjan. They also meet hosts Ivory Coast and Guinea Bissau in their group matches.