Manchester United manager Sir Alex Ferguson apologised to United fans after his side were beaten 2-1 by Championship team Crystal Palace in the League Cup quarter-finals on Wednesday.

Ferguson was upset with the manner of his side’s defeat, which also saw the Da Silva twins and Dimitar Berbatov forced off with injuries.

Bulgarian striker Berbatov appeared to have suffered an ankle problem in the opening stages and left Old Trafford with a plastic boot on the injured leg and looks sure to miss tomorrow’s game at Aston Villa.

Palace will now face fellow Championship side Cardiff in the semi-finals, while Manchester City face Liverpool in the other tie.

The defeat to Palace was the ninth time that United have lost a League Cup match to lower-league opposition since 1990 and Ferguson was baffled by his team’s display.

“I really apologise to our fans because that was not a Manchester United performance,” Ferguson said.

“I don’t want to take anything away from Palace and I want them to get to the final because it was a mammoth effort and they worked their socks off so we’re just very disappointed.

“When it went to extra time I thought we must win it but it wasn’t to be. We had a lot of possession but didn’t do anything with it.”

Ferguson had promised to blood some youngsters at Old Trafford but Ezekiel Fryers, Ravel Morrison and Paul Pogba had to settle for coming off the bench.

But despite the frustrating nature of the defeat, Ferguson insists the youngsters will not have been damaged by the ­experience.

“It was hard for them to come on when the team isn’t playing well around and about them but it won’t do them any harm,” Ferguson said.