Below-par United take step towards title 20

Manchester City's defeat at Everton earlier in the day paved the way for United to extend their advantage and the all-time top-flight record for the largest title-winning margin -- the 18 points by which United won the 2000 championship -- is now under threat.

United also enjoyed a strong outing from defender Rio Ferdinand, who manager Alex Ferguson confirmed is due to link up with the England squad this week despite concerns over his long-term fitness.

Reading, under caretaker manager Eamonn Dolan, ended a traumatic week in which they had parted company with Brian McDermott with a creditable performance, but one which still leaves them deep in trouble near the foot of the table.

Rooney scored what looked likely to be an important opening goal after 21 minutes, although the architect of the effort was Ferdinand, the centre-back recently recalled to Roy Hodgson's England squad.

Ferdinand's burst of power and pace allowed him to slip the ball through to his international team-mate, who unleashed a shot from the edge of the area that deflected off defender Alex Pearce and looped over goalkeeper Stuart Taylor into the net.

Ashley Young had signalled the first moment of real attacking intent after 20 minutes, collecting a fine cross-field pass from Ferdinand and sending a well-struck cross inches beyond the lunge of Robin van Persie.

Taylor was forced to rush from his line to beat Young to a dangerous Ryan Giggs pass and, with the goal soon following, United wrapping up victory seemed an imminent formality.

Danny Welbeck certainly thought so, surging forward and shooting inches wide from distance, while Rooney tested Taylor's handling, also from long range.

But to the credit of Reading, and caretaker manager Dolan, they did not fold and actually enjoyed the better of the remainder of the first half.

Neat approach play from Nicky Shorey and Garath McCleary set up Hal Robson-Kanu for a curling effort that just missed the United goal and Jobi McAnuff then darted to the by-line, from where he sent a teasing centre across the face of goal.

Reading maintained the pressure after the restart, with United defender Nemanja Vidic fortunate to escape a penalty appeal after he appeared to push over Adrian Mariappa at a corner.

It was a tense period for the champions-elect, although they emerged from it with a period of pressure of their own, one sparked by the unlikely source of left-back Alexander Buttner, making a rare start for United.

Only Jem Karacan's well-timed tackle halted his progress on goal and, in quick succession from the subsequent corner, van Persie, Welbeck and Young all had shots that failed to test the opposition goalkeeper.

The same was certainly not true of a 64th-minute free-kick from van Persie, who beat the wall, from 20 yards, and saw Taylor parry his attempt with a smart dive low to his left.

Ferguson brought on Michael Carrick, to strengthen a midfield that had been second-best too often, and he started a move that ended with an attempted chip from Rooney that comfortably cleared the Reading goal.

Carrick was also involved in a move, featuring Giggs and van Persie, that culminated in the Welsh veteran having a near-post shot well saved by Taylor.

It was not until the 85th minute, and a tremendous strike from Rooney at the edge of the area, that the Reading goal was seriously threatened.

His effort cleared the target by inches, while van Persie almost succeeded with a spectacular bicycle kick from substitute Shinji Kagawa's injury-time centre.