Three European Cups, one Cup Winners' Cup, one European Super Cup and two Club World Cups are the seven international titles won by the Red Devils, but they have a spot in their trophy cabinet waiting for the Europa League trophy, which they will fight for on Wednesday in the final against Ajax.
The Europa League (formerly known as the UEFA Cup) was never a priority for the team lead by Sir Alex Ferguson, who always performed well in the Champions League. Since the Scottish manager's departure, United have struggled in European football altogether.
It is true English clubs have never focused on continental tournaments as much, with the exception of the Champions League. All that changed this season, after a poor display in the Premier League, Mourinho's side decided to turn all of their attention to the Europa League, which would also award them a way into the Champions League.
By winning the final in Stockholm (19:45 GMT) against Ajax, the Red Devils would not only increase the number of English teams in the Champions League to five (Chelsea, Tottenham, Manchester City and Liverpool), but they would also lift their first European trophy since 2008.
A competition which began as a mere distraction has become a primary focus. Mourinho's team overcame Fenerbahce, Feyenoord and Zorya Luhansk in the group stages, and Saint-Etienne, Rostov, Anderlecht and Celta Vigo in the subsequent knockout phase. Their objective is now to be crowned champions in order to qualify for the Champions League and complete their trophy cabinet.