Former England manager Sam Allardyce has insisted that “nobody thought” Manchester United would follow through with one decision under Sir Alex Ferguson’s time at Old Trafford. Manchester United legend Sir Alex Ferguson is widely regarded as one of the best managers of all time after a prolific legacy in both Scotland and England. The 82-year-old former United manager left Old Trafford at the end of the 2012-13 season after leading the Red Devils to their last Premier League title. Ferguson ushered in an incredible period of success at United, including capturing 13 Premier League titles, two …