The Red Devils get the chance to recover from that disastrous result in the Capital One Cup against old rivals Liverpool on Wednesday and Rooney is desperate to contribute to what would be a morale-boosting victory.
"Fair enough, City deserved the victory. We gave sloppy goals away. As I said before, it is not good enough," said Rooney who netted United's late consolation goal.
"It is nice to score but it means nothing. It is a bad day for us but we have another big game against Liverpool on Wednesday.
"We will forget about this now and try to move on in that one. It is the ideal game. Any game against Liverpool is a big game, whether it is a friendly or Capital One Cup or Premier League. It is still massive."