Manchester United's Robin van Persie was stretchered off the field Wednesday after scoring a hat trick against Olympiakos to keep the Red Devils alive in the Champions League.
Peter Byrne/Press Association/AP

MANCHESTER, England (AP) - Manchester United's Robin van Persie will miss up to six weeks with a left knee injury, ruling the Netherlands striker out of both legs of a Champions League quarterfinal against Bayern Munich and potentially six Premier League games.

It is a major blow to United's hopes of winning the Champions League, the club's only realistic route back into Europe's top competition next season.

Following a second scan on the injury on Friday, United said Van Persie has a ''sprained knee which will keep him out for around 4-6 weeks.''

He appears to be in no danger of missing the World Cup finals in Brazil beginning in mid-June - the worst-case scenario according to United's diagnosis is that Van Persie is out until the start of May, leaving him available for the last two or three league games in United's season.

LYTTLETON: Van Persie's hat trick saves Manchester United

Van Persie, who has scored 23 goals in 29 games for club and country this season, was carried off on a stretcher after hurting his knee in a challenge from behind toward the end of Wednesday's 3-0 victory over Olympiakos, in which he scored a hat trick to send his team into the last eight.

United is seventh in the Premier League after its humiliating 3-0 loss to Liverpool last weekend, 12 points behind fourth-place Manchester City having played two more games.

A finish in the top six would qualify United for next season's Europa League, and sixth-place Everton is three points ahead with a game in hand.

It will be a second significant spell on the sidelines for Van Persie this season - he played just two games across 2 1/2 months over the turn of the year because of groin then thigh problems.

Read More:

CHAMPIONS LEAGUE: United draws Bayern Munich in quarterfinals

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