Nigeria's Emmanuel Emenike undergoes knee surgery

Nigeria striker Emmanuel Emenike

Nigeria striker Emmanuel Emenike underwent knee surgery on Thursday and will be out for six weeks.

It means the 25-year-old, who was joint top scorer at this year's Africa Cup of Nations, will miss World Cup qualifiers against Kenya and Namibia next month.

"Emenike underwent a successful operation on his meniscus and will miss four to six weeks," his Russian club Spartak Moscow said on their website.

The forward will miss the last four games of the season in Russia.

His absence will be most keenly felt by the Super Eagles, who are level on points with Malawa at the top of their World Cup Group F.

After three matches both sides have five points, with only the top team in each group going through to the next round of qualifying for a place at the tournament in Brazil next year.