The manager claims Crystal Palace's winning goal was offside as the Premier League's second place team are knocked out of the Carling Cup.
Ferguson: Manchester United are not getting luck from officials
Sir Alex Ferguson again used the performance of the officials to explain another poor display at Old Trafford from his side, this time at home to Crystal Palace in the Carling Cup.
Glenn Murray headed an extra-time winner as the Championship outfit claimed a memorable 2-1 quarter-final win but the Manchester United manager was critical of the decision making of the assistant referee, believing the winning goal was offside. On Saturday, he described the decision by John Flynn to award a penaty against Rio Ferdinand for a tackle on Hatem Ben Arfa as "an absolute travesty".
"Obviously the goal was offside - the second goal - from what I have seen," Ferguson said. "We are not getting any luck from linesmen just now but I can't take that away from Crystal Palace. They fought hard to get the result and they deserve it."
Ferguson paid tribute to the visitors but was far from impressed by the performance of his own players.
"I don't know where to start to be honest," Ferguson told MUTV. "My apologies are to the fans because that was not a Manchester United performance.
"I don't want to take anything away from Crystal Palace. I wish them every success and hope they get to the final because it was a fantastic, mammoth effort from them tonight. Every one of their players worked their socks off to try to get to the semi-final. I am just very disappointed."
Palace took the lead with a stunning goal from Darren Ambrose on 65 minutes but United looked the most likely to progress after Federico Macheda replied from the penalty spot.
Yet Palace dug deep and grabbed the winner in the 98th minute when Murray, despite being close to straying offside, nodded in an Ambrose free-kick.
Ferguson said: "When it went to extra time I thought we must win but it was not to be."
Palace will now play Cardiff in a two-leg semi-final for a place at Wembley, having avoided big guns Liverpool and Manchester City in the draw.
The London side had gone to Old Trafford without scoring in their previous five games but manager Dougie Freedman felt his players showed great spirit and determination.
He said: "They should be proud of themselves. They stuck together and I think that was a really good cup tie between two teams who gave everything.
"In the last 15-20 minutes of extra time the desire shone through in the end.
"That is what they should be proud of.
"Sir Alex has a wonderful team, they kept on going.
"We had to dig in and show that hunger and desire to see the tie through and that is what they have done.
"There was no tactical genius. We had to dig in.
"I felt we had a good gameplan and I thought every single player stuck to our gameplan."
Despite having two of the Premier League's top six in the draw for the last four, Freedman felt his side had been handed the toughest of assignments next up in fellow Championship side Cardiff.
He said: "It is going to be difficult because I've played against Cardiff and got beaten.
"I've also had the pleasure of seeing them a few times and they are a very good side.
"It's probably the hardest draw, to be honest.
"They are up at the top of the Championship and it is going to be very difficult for us.
"But I am just proud of the lads, to get through to the semi-finals from where we have come from in the last couple of years - relegation zones and administrations.
"We will enjoy tonight and approach that when it comes along."