Sir Alex Ferguson has promised a response from his Manchester United side after they were humiliated 4-1 by Liverpool at Old Trafford.
The Reds produced a stunning come from behind victory to breathe fresh life into the Premier League title race.
United's performance was undermined by a host of defensive mistakes and their afternoon went from bad to worse when Nemanja Vidic - who was at fault for the first goal - was sent off for a professional foul on Steven Gerrard midway through the second half.
But after seeing his side's lead over the Reds cut to four points, Ferguson has promised a response.
"It's difficult to defend a 4-1 defeat," he said. "We got in front and then threw the game away. It's a hard one to take.
"But at this club it's always about how you respond. When you lose a game you respond and that is what we will do."
However, Ferguson doesn't believe a first league defeat since November has overly damaged United's title chances.
The Red Devils still have a game in hand on closest rivals Liverpool and Chelsea.
He added: "It was one of those days, we made uncharacteristic mistakes. In big games you don't want to do that.
"If you win 4-1 at Old Trafford you deserve the plaudits, you can't deny Liverpool that.
"But if the league was starting today, you'd take a four-point advantage with a game in hand.
"The goal difference is narrowed, it's only five goals now. It was a bad day, but we have to kick on."