Ferguson:
"I was flabbergasted by our performance.
"There was no mitigation. These are all young players we have shown great hope in and have trumpeted in a loud way in recent years. It was a big shock to us all. We were second to every ball. Over the 90 minutes we were disappointing, but I have to give the young players a chance so it was no surprise to see us ring the changes.
"We have trumpeted these young lads a lot, so what happened tonight was a big shock for us all.
"You want to give these boys a chance and we have not had the opportunity to do that. The number of Coventry fans who came made it a real cup-tie atmosphere and maybe that was an issue for some of our players because in the first half, we were second to every ball.
"You hope that the young players will look at it and want to improve themselves. Their temperament - against a team who were ready for a cup tie - was certainly an issue in the first half, so maybe they are not used to that kind of cup-tie football.
"But we will keep giving youngsters their chances. We have been doing it for years now and these players have to have games."
Iain Dowie [Coventry manager]:
"This will go down as a great night for Coventry.
"We forced United to make their changes early, they had made all their substitutions by 55 minutes. I have been here as a player and a manager and never done that well so hopefully this result will give us all some belief because I feel we deserve it."
"Not seeing players like Rooney, Ferdinand, Scholes and Vidic on the team-sheet is a benefit. To talk about players that weren't here, though, would be a travesty for Coventry City.
"I knew I would get a response after Saturday's 4-1 defeat to Ipswich, and the team deserve to be applauded. Now we want to take this into the league, starting with Saturday's tie against Charlton, because that's what our bread and butter is."