Nigeria's leading player John Obi Mikel was ruled out of the World Cup in South Africa Saturday, joining a lengthening big-name casualty list with a severely bruised ankle. He picked it up on his first day back in full training following a separate knee injury, a week before the month-long tournament kicks off Friday. The 23-year-old joins Ghana's Michael Essien (knee injury) and very probably the Ivory Coast captain Didier Drogba (broken bone near elbow) on the sidelines, leaving the finals likely to miss three of its biggest African names. Obi Mikel learned Saturday that he would miss this month's showpiece (June 11-July 11) after a scan showed he would not recover in time. Nigerian Football Federation (NFF) spokesman Idah Peterside said Nigeria's key midfielder had pulled up after some 50 minutes of training in Richards Bay Friday with severe pain. “He had been complaining about a niggle in the ankle when we first arrived in South Africa but after training Friday it really flared up. His knee was doing fine and you can understand he is devastated about this new problem. He is not sure how it happened. It wasn't a tackle with another player or anything like that,” Peterside said. “It was been very emotional for him and for the other players too. The team has been trying to consol him. He's been to the Olympics but this was to be his first World Cup.” Obi Mikel will return to London for further medical examinations at the weekend, the spokesman added. Hiddink rules out Liverpool job, but Eriksson keen Guus Hiddink has ruled himself out of the race to become Liverpool's new manager, but Sven Goran Eriksson admits it would be a dream to take charge of the Reds. Hiddink has been linked with the vacant Liverpool job since Rafael Benitez departed Anfield by mutual consent Thursday. The 63-year-old enjoyed a successful spell in the Premier League as interim Chelsea boss in 2009, but the former Australia manager has just taken over as Turkey coach and has no intention of walking out on his new employers. Hiddink's agent, Cees van Nieuwenhuizen, told BBC Sport: “Guus has shown over the years that he is loyal to agreements that he signed. There is no reason today why he would change such behavior. The Reds are believed to be looking at several other candidates including Aston Villa boss Martin O'Neill and Fulham's Roy Hodgson. One man who could be interested in the Anfield post is Ivory Coast coach Eriksson. The former England boss gave a strong indication that he would be ready to succeed Benitez after revealing he supported Liverpool as a boy. Eriksson told The Sun: “I have been a Liverpool fan all of my life. I never mentioned it when I was in charge of England because I didn't think it was fair.” Uzbek referee to officiate World Cup opener Uzbek referee Ravshan Irmatov has been assigned Friday's opening World Cup match between Mexico and South Africa. Carlos Simon of Brazil gets the high-profile game between the United States and England Saturday. Friday's other opening-day match, France vs. Uruguay, will be officiated by Yuichi Nishimura of Japan. In Saturday's other games, Wolfgang Stark of Germany will handle Argentina vs. Nigeria, while South Korea vs. Greece will be refereed by New Zealand's Michael Hester. Two Mexicans will officiate early games. Mexico's Marco Rodriguez has Germany vs. Australia on June 13. Countryman Benito Archundia will referee Italy vs. Parguay on June 14. The first 16 officiating assignments were announced Saturday night by FIFA.