Sir Alex Ferguson's side was more than aided by the benevolence of referee Mike Riley who sent off Southampton's Matt Paterson for violent conduct in the first half and then incorrectly awarded United a second-half penalty.

Goals from Danny Welbeck, Nani and substitute Darron Gibson earned United a simple passage into the next round.

Birthday boy James Milner grabbed both goals as Aston Villa reached the fourth round of the FA Cup for only the second time in eight seasons - but it was given a scare by Gillingham.

Milner gave Villa a 2-1 win from the penalty spot 13 minutes from time after Adam Miller was adjudged to have fouled Ashley Young in the box.

Until then it had looked like the Gills would earn a deserved - and lucrative - replay after Simeon Jackson blasted in his 12th of the season to cancel out Milner's well-taken opener.

The FA Cup fourth round draw is:
Birmingham/Wolves v Middlesbrough
Cardiff v Arsenal
Chelsea/Southend v Ipswich
Cheltenham/Doncaster v Aston Villa
Derby v Nottm Forest
Hartlepool v West Ham
Hull/Newcastle v Millwall/Crewe
Kettering v Fulham
Leyton Orient/Sheff Utd v Charlton/Norwich
Liverpool v Everton
Man Utd v Tottenham
Portsmouth/Bristol City v Histon/Swansea
Sunderland v Blyth/Blackburn
Torquay v Coventry
Watford v Leicester/Crystal Palace
West Brom/Peterborough v QPR/Burnley
Matches to be played over the weekend of January 24-25.