File photo dated 21/05/2008 of Manchester United manager Alex Ferguson celebrates with the trophy after winning the UEFA Champions League Final at the Luzhniki Stadium, Moscow, Russia. PRESS ASSOCITAION Photo. Issue date: Wednesday May 8, 2013. Sir Alex Ferguson will retire at the end of this season, Manchester United have announced. See PA Story SOCCER Man Utd. Photo credit should read: Owen Humphreys/PA Wire.