Nemanja Vidic has said that Manchester United must learn lessons from today's defeat to Manchester City.
The Premier League champions lost 4-1 at the Etihad Stadium - a hammering that the Serbian defender describes as "horrible".
"From the first minute City tried to be aggressive and had more possession in the first 20 or 30 minutes," the 31-year-old told Sky Sports News. "We didn't really get in the game from the first minute.
"This is what we have try to learn from. We can't look back. It's horrible to lose the derby - it's worse when you lose in this way.
"We were never close to winning the game. That's disappointing. We have to come back but from tomorrow we start to be positive and move on."
United will look to get back on track when they welcome West Bromwich Albion to Old Trafford next Saturday.
