London, Apr 9 : Manchester United striker Wayne Rooney is a major injury doubt for coach Sir Alex Ferguson as he bids to stop his club's season going down the pan.

Rooney was hit hard on the ribs by the ball at the end of the first half of the Red Devils' 2-2 Champions League quarterfinal first leg at home to Porto on Tuesday night.

He bravely played on, but was clearly in some discomfort as he left the ground after the game, The Sun reported.

Striker Rooney will be checked today and the hope is that he has only heavy bruising. But even that could keep him out of Saturday's trip to Sunderland.

United have lost two of their last three Premier League games and only won Sunday's home clash with Aston Villa 3-2 thanks to a last-gasp goal.

They gave up a 2-1 lead against Porto to draw 2-2.

It is now likely they will have to become the only English club to win at Porto if they want to progress into the semis.

And with Dimi Berbatov still out with an ankle problem, it will be a massive blow to be without Rooney.

Boss Ferguson is also sweating over Rio Ferdinand, who has a groin injury. Fellow defender Jonny Evans is likely to miss the game with a similar problem. (ANI)