But now bragging rights will have to be shared by both the red and blue half of Manchester.
Pep Guardiola’s side secured the Treble by overcoming Inter 1-0 in a closely-fought contest.
And they will look back on the moment they emphatically earned revenge on Real Madrid in the semi-finals as the highlight of the season.
After a dramatic exit in last year’s semi-final where Los Blancos netted two last minute goals to force extra time before qualifying on aggregate, City drew Carlo Ancelotti’s men again in this year’s final four.
City secured their second trophy of the Treble last weekend as they stuck the knife into rivals United by winning the FA Cup final at Wembley.
Ilkay Gundogan netted both goals as the Red Devils tried in vain to end their hopes of emulating the achievements of Sir Alex Ferguson’s side in 1999.
The Treble had looked out of reach at the turn of the year when it looked like they would miss out on the Premier League title which they had won in four of the previous five seasons.