City clinched the title without kicking a ball as their arch rivals United slumped to a shock 1-0 defeat against West Bromwich Albion on Sunday.
Jay Rodriguez’s second half header for bottom of the table Albion sparked wild celebrations among City players and fans across Manchester.
City captain Kompany watched the match at the house of his Mancunian wife Carla Higgs, who invited her United-supporting father to join the party.
The gathering was captured in a social media post and Carla’s father is seen wearing a United shirt as Kompany celebrates.
“It shows how football is lived in Manchester as we have Reds in the family and Blues but today was a day for the Blues. It is banter. It’s been a great day,” Kompany said.
Kompany was caught on camera speaking with his City team-mates Kevin De Bruyne and Kyle Walker on Face-time to celebrate the success, with Carla’s grand-mother heard asking him “Do they want to come round?”
Kompany has been at City since 2008, playing a key role in the club’s emergence as a genuine force in the English game.
The 32-year-old has featured in all three of City’s Premier League triumphs, as well as their FA Cup and League Cup victories.
But Kompany has yet to help City retain the title and he admitted he would love to secure back to back Premier League triumphs.
“You can’t take (winning the league) for granted, I’ve won three now but there’s so many we’ve missed,” he said.
“My team-mates will roll their eyes as I want to see the reaction from us next season as I’ve never been able to retain a title.”
City manager Pep Guardiola didn’t bother to watch the United game, opting for a round of golf with his son Marius.
However, Kompany was glued to the action, even if he found it hard to watch his team’s destiny in someone else’s hands.
“I had a feeling when I woke up this morning. I don’t like to wait and see a team lose so it was different experience today,” Kompany said.
Guardiola is the first Spaniard to manage a team to the English top-flight title.
The former Barcelona and Bayern Munich boss had already led City to League Cup final victory over Arsenal this term.
It completes an impressive revival from City, who failed to win a single prize last year.
And Kompany was quick to pay tribute to Guardiola for getting the best out of his players in his second season.
“I have learnt from him. When I was 20 I would have been a perfect player for him,” he said.
“Everyone that plays under him will have had success because of him, because he has the ability to unlock the full potential.”
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