#2: The first Champions League trophy (2008-09)
The 2008-09 season has to go down in history as the best season of the club. Guardiola's arrival was welcome, but no one had expected the way in which the young coach would make the world his own.
Many coaches have won a trophy in their first ever season as a manager. But a treble in the debut season? Only Guardiola can boast about that. After winning the Copa Del Rey and the La Liga, Barcelona were up against defending champions Manchester United in the Rome 2009 Champions League final.
Guardiola proved his mettle again as a sturdy Barcelona outclassed United in a 2-0 victory, completing the treble in style.
Defeating a shrewd tactician like Sir Alex Ferguson was one of the greatest achievements for Josep Guardiola at a young age. Of course, he would repeat the feat in 2011 at Wembley, winning his second Champions League title in three years.