Manchester United midfielder Anderson has been ruled out for the rest of the season with a knee injury and will also miss the World Cup.

The Brazilian, who has struggled to keep a regular place in the starting line-up this season and is only on the fringes of the national squad, was injured in the first half of United’s 3-0 victory over West Ham on Tuesday.

United manager Alex Ferguson said on Thursday that Anderson had ruptured his cruciate ligament and would be out of action for six months.

“It is a bit of a blow to us, particularly with the AC Milan game coming up because Michael Carrick is suspended,” said Ferguson, whose team leads the Serie A side 3-2 from the away leg and will face Milan at home on March 10.

“It is strange. When you see cruciate injuries it is usually something simple. He stretched out for the ball and his knee just popped. ”

Ferguson said Anderson needs surgery to repair the injury but that will not happen for two more weeks.

“We have assessed the situation and know he needs the operation,” the United manager said. “That will be done in two weeks’ time in Portugal once the swelling has gone down.

“Sometimes we have sent them to Dr. (Richard) Steadman in Colorado. In this instance he is comfortable with the surgeon he has dealt with in Portugal in the past. He will be out for six months and hopefully that should have him about right for the new season.”

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