Chelsea midfielder John Obi Mikel has been dropped from Nigeria's World Cup squad.

Obi Mikel has been struggling to shake off a knee problem after undergoing surgery in recent weeks and has now told his country's football bosses he did not want to put the injury into further risk.

"We have dropped Mikel from the World Cup after he told the team he did not want to put his career at risk as his knee injury has yet to fully heal after a recent surgery," team co-ordinator, Emmanuel Attah, told mtnfootball.com.

Mikel has been closely monitored since joining his team-mates at their pre-tournament training camp on the outskirts of London a week ago, with coach Lars Lagerback repeatedly giving reassurances over his fitness.

He was rested in a game against Colombia over the weekend and the Swede explained "there was nothing wrong, but it was just a precaution".

Yesterday, the 23-year-old trained fully with the rest of the squad for the first time since they arrived at their World Cup base in Durban.

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