The Treble is a term used in football to denote a club winning their country’s top league competition, the main domestic cup and the continent’s main club competition all in the very same season. ‘Doing the treble’ is said to be a remarkable feat for any football club.
Reigning Premier League and European champions Manchester United achieved this feat in the 1998-1999 season when they won the Premier League, the FA Cup and the UEFA Champions League. They were said to have done the European Treble.