Irwin began his career at Leeds United, where he made over 80 appearances for the club, before joining Manchester United. Having paid £625,000 for the defender, Sir Alex Ferguson later described Irwin's signing as 'pound for pound, the greatest ever'. Irwin won seven Premier League trophies, three FA cups, a League Cup, the Champions League and Cup Winners Cup during his time at Old Trafford. A free-kick and penalty specialist, Irwin played 56 times for his country.