"Look at us now," Vidic told Manchester United Radio. "We're playing better than ever and we're only point behind Arsenal in the league. I think losing to City was a wake-up call and helped us realise that if we don't play to our best then we won't necessarily win."
Since that loss, United have chalked up four victories and a draw in Europe away from home.
"We're doing well right now and I hope we'll keep this momentum going," Vidic says.
"I want to play in the big games and win trophies; that's why I'm at Manchester United. Every game is crucial now and it's important we keep our shape and don't lose too many goals."