Rather than dwell on the loss, Rooney wants the Reds to bounce back quickly against Aston Villa on Saturday, in order to restore confidence ahead of next week’s Champions League clash with Bayern Munich.
The striker told MUTV: "It's a bad night and we didn't deserve to win. We weren’t clinical enough and we didn't create enough chances.
"No-one likes to lose a derby game – they're big games and they're great to win, but when you lose it's not a great feeling. For the fans and for us, we have to win more and stay together.
"It was a poor start – I'm not even sure whether we touched the ball before they scored. After that, I thought we did okay and got back into the game a little bit before half-time. But we started the second half on the back foot and their second goal was a killer.
"We've got two big games coming up against Bayern Munich but first we have to focus on the Villa game and try to end the season on a positive note."