The Italian striker hopes that feeling will linger into future battles between the Manchester giants.
He said: "It was better to win like that than 6-0, when you are sure to win.
"United have suffered a little bit, it is better for us.
"When I was on the bench, warming up with Micah Richards and they scored their second goal, Micah was upset but I said 'Don't worry, we will win'.
"That's what we did. I thought it was really possible. I believed in it and I was right."