Vinicius Junior struck the hosts ahead before the interval, before De Bruyne's ferocious strike levelled the score after 67 minutes.
The Belgian, who was named Player of the Match at the Santiago Bernabeu, now has 11 knockout goals in the Champions League, the most by any City player in the history of the competition.
Grealish had nothing but praise for his teammate after the draw.
"In the end, Kev [De Bruyne] comes up with an absolute worldie. So buzzing for him.
"He's chilled, man. That makes him who he is. He's a laid back, calm guy. Nights like this are made for him.
"You can't count how many times he's scored important goals and got important assists.
"In these big games, it must have meant a lot for him. I'm obviously buzzing for him.
"We all know what a great guy he is and what a brilliant player he's been for this football club. Nights like tonight sum him up really."
The Englishman also provided his overall assessment of the result, paid special tribute to City's mental strength and touched on our incredible run of form.
Watch the entire interview via the video at the top of the page.