Juve were deserved 2-0 Champions League winners in Turin on Wednesday night.
McKennie struck on the night and remarked afterwards: "A great evening, it was important to win this match after so many draws in the league. These three points against such a strong team as City are very important to gain confidence, to bring Juventus back to the top.
"This is a victory for the group, we talked about it yesterday: we need to do more, stay connected, win the tackles, go back and forth, it's very nice to see.
"City? Many teams go through difficult moments, they are a strong team but they are having a difficult moment, they played well anyway."
He added: "My Harry Potter celebration? I've already done it against Barcelona and I hope to do it many more times."
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