Grealish struggled to make an impact at the Ataturk Olympic Stadium as Inter frustrated City’s star-studded attack.
And though he acknowledged he wasn’t happy with his display after full-time, he couldn’t contain his emotions as he expressed his delight.
He told BT Sport: “It’s what you work your whole life for, isn’t it? I’m just so happy, man. I played so c**p today. Honestly, I was awful, but I don’t care.
“To win the treble with this group of players is so special. Anyone that knows me knows how much of a family person I am and how much I love football and stuff. This is what I’ve worked for my whole life.
“You think back to all the people who have helped you along the way, and just seeing my family there in the crowd makes me emotional.”
And he then directed his praise toward Guardiola, the coach who splashed a then-British record £100million to sign him from Aston Villa in 2021.
“He’s just a genius, isn’t he? I just said to him then, ‘I want to thank you because you’ve made this happen for me’,” Grealish explained.
“He put so much faith in me, buying me for a lot of money. Even last year, when I was playing c**p, he stayed there with me [and] spoke to me.
“And then this year, he’s given me that platform to go and perform. I just said thank you to him.”
City’s European success marks a significant moment, given it’s not just the first time the club are the champions of the continent.
Guardiola has guided the Citizens to the treble by winning the Premier League, FA Cup and Champions League in the same season.
It matches bitter rivals Manchester United’s historic accomplishment from 1999, beating Erik ten Hag and co. on the way in last weekend’s FA Cup final.
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