Sir Alex Ferguson admitted he was in shock after seeing his Manchester United team throw away a two-goal lead with less than ten minutes to play on Sunday, resulting in a surprise 4-4 draw with Everton at Old Trafford.
The Red Devils boss has now urged his players to respond to their latest setback in next Monday's all-important derby clash against Manchester City at the Etihad Stadium.
"It was a throwaway, an absolute giveaway," exclaimed Ferguson in his post-match interview. "We just needed to see the game out and it was a travesty because some of our football was fantastic.
"The goals we scored were great goals. To give away four goals at Old Trafford in a home game like that which was so important to us is unbelievable. I can't believe it.
"We've given ourselves a real task at the Etihad. We'll go there only three points ahead."
Ferguson was pleased with the attacking intent shown by his players yesterday, with Wayne Rooney and Danny Welbeck particularly impressing against the Toffees.
However, United were let down by a poor defensive display, leaving David Moyes' players too much time and space to get back into the game.
"We've created our goals with really good football but I think they got their goals easily," he continued. "Defensive lapses have cost us.
"Rooney and Welbeck were a real threat to Everton today, their combination play and understanding of each other was terrific. They should have got more out of the game than they did.
"In previous matches recently we've actually defended very well. But this was a bad performance defensively. It was a real blip for us today to get a performance like that. I think the goals we conceded were soft goals."
Manchester City responded with a comfortable 2-0 victory over Wolverhampton Wanderers at Molineux, putting the Citizens back in the driving seat in terms of the Premier League title race, whilst also relegating Terry Connor's side in the process.
Ferguson added: "We've given City the initiative, there's no question about that. It makes the game at the Etihad Stadium a really important game now. It makes it the title decider really.
"We make it hard for ourselves but we have to go there knowing we're capable of getting a result.
"There's no reason why we can't do that. There's been an expectancy from City that this could be their decider. But it's our decider too."