Dimitar Berbatov scored the first goal, while English international Wayne Rooney doubled the score.
United starting lineup was boosted with Van der Sar. Also Nani, who reports suggested he is about to leave the club, has been given a chance to play for 90 mins.
The first goal came in second half, Rooney passed to Dimitar Berbatov and he got around Michael Duff before slotting home across Jensen, although it took a deflection off Duff.
In the 69th mins, Rooney scored the second goal, Berbatov shot from the right and Jensen made a great save but he was unlucky as the ball rebounded to Rooney and he took a breath before placing into the right corner from ten yards.
In the stoppage time, Diouf managed to spring the offside trap from Anderson throughball and reached the ball first to head it home and celebrate his first goal with an aerobatic jump!
The result means Man United stay a point behind leaders Chelsea – who thumped Sunderland 7-2 – having played a game more.
Meanwhile, Dimitar Berbatov may need a knee operation after feeling the pain again during the game.