Wes Brown took advantage of some sloppy goalkeeping by Jose Reina to open the scoring in the 34th minute.

Liverpool hopes of claiming an equalizer suffered a major blow when Javier Mascherano was sent off for dissent.

Ronaldo capitalized on another mistake from Reina to double United's advantage in the 79th minute. Nani came off the bench to complete the rout two minutes later.

United are in charge of the Premiership table with 73 points, six points ahead of second-placed Arsenal, who face Chelsea later in the day.

Reina almost gifted United the lead in the 33rd minute when a harmless cross slipped out of his hands. He reacted quickly to palm the ball away.

The former Villarreal guardian was at fault for Brown's opener just one minute later after The England defender got ahead of him to head home Wayne Rooney's in-swinging cross.

Referee Steve Bennett widened Liverpool's misery shortly before the break when he handed Mascherano a second booking for remonstrating.

United capitalized on their numerical advantage in the second half to seal a comfortable win.

Reina produced some fine saves to deny the hosts on several occasions but the Red Devils managed to break his resistance through in-form winger Ronaldo.

The Portuguese atoned for wasting a clear-cut opportunity moments earlier to double United's lead in the 79th minute when he rose to head Nani's corner into the back of the net.

Reina was once again the culprit after his mis-timed jump allowed Ronaldo to kill off Liverpool hopes.

Substitute Nani put the icing on the cake with a powerful bullet from inside the area.