Jose Mourinho endured a torrid return to Stamford Bridge on Sunday as Chelsea hammered Manchester United 4-0 in the Premier League.
Here, Press Association Sport charts five of United's heaviest league losses.
Manchester United 1 Manchester City 6, October 23, 2011:
The first time United had leaked six goals at Old Trafford since 1930, this was their heaviest home defeat for 56 years. Mario Balotelli started the rout as City kick-started their title drive.
Newcastle 5 Manchester United 0, October 20, 1996:
Phillipe Albert's stunning lob over Peter Schmeichel capped a thumping win as Kevin Keegan's men gained some revenge having lost the title to United the previous season.
Chelsea 5 Manchester United 0, October 3, 2000:
Chelsea ended United's 29-game unbeaten run in some style, Gus Poyet on the scoresheet after just 27 seconds.
Southampton 6 Manchester United 3, October 26, 1996:
Egil Ostenstad fired a hat-trick, Roy Keane was sent off and Matt Le Tissier chipped Schmeichel. Arguably more humiliating than United's 3-1 defeat at The Dell that Sir Alex Ferguson blamed on the side's grey kit.
Manchester United 1 Liverpool 4, March 14, 2009:
Fernando Torres ran riot with Steven Gerrard, Fabio Aurelio and Andrea Dossena also on target as Rafael Benitez got one up on Ferguson. Despite this home humbling, United still progressed to take the title.