Updated: May 08, 2013, 12:00 AM
In pictures: Sir Alex Ferguson's career at Man Utd
Manchester United manager Sir Alex Ferguson (L) holds up the trophy after beating Chelsea in the final of the UEFA Champions League football match at the Luzhniki stadium in Moscow on May 21, 2008. The match remained at a 1-1 draw and Manchester won on penalties after extra time. AFP PHOTO / Adrian Dennis
Sir Alex Ferguson and his assistant manager Brian Kidd hold the Premier League trophy after clinching a second league and FA Cup double in the 1993-94 season. ShaunBotterill/Allsport
Manchester United manager Alex Ferguson and keeper Peter Schmeichel celebrate their dramatic 2-1 win against Bayern Munich to win the Champions League in 1999. Phil Cole / Allsport
Ole Gunnar Solskjaer scores the second and winning goal for Manchester United deep in injury time against Bayern Munich in 1999. Picture: Allsport
Sir Alex Ferguson watches Manchester United for the first time in a 2-0 defeat against Oxford United at the Manor Ground in 1986. Picture by PA
Mark Robins celebrates scoring for Manchester United in their FA Cup third round tie away at Nottm Forest in 1990. Speculation at the time was if they had lost the tie, Sir Alex Ferguson would've been sacked. Steve Etherington / EMPICS
Sir Alex Ferguson argues with officials after the Portuguese midfielder Nani is sent off during their Champions League tie against Real Madrid this year. United lost 3-2 on aggregate. Pierre-Philippe Marcou / AFP Photo
Manchester United players and fans celebrate United's record 19 Premier League titles in 2011. United added a 20th title this year. Paul Ellis / AFP Photo