When Nemanja Vidic headed the Red Devils in front after just four minutes, Ferguson thought he was in for a night to remember.

Instead, it was nearly one to forget as United's play deteriorated, with the crossbar and then half-time coming to their rescue before Cristiano Ronaldo sealed victory with a second goal just after the restart.

"It was a long European night," sighed Ferguson.

"I didn't know if it was a game of football or a game of suicide.

"We started off very well and once we scored the first goal I thought we would go on and kill them.

"But then we opened the door for them with too many flicks, backheels and passes into space and were lucky to be in front at half-time."

Had Zlatan Ibrahimovic seen his downward header bounce up and into the net rather than onto the crossbar, the outcome could have been drastically different.

Instead, United advance to the March 20 draw with the other three English contenders who make up half the remaining field, proving beyond doubt the Premier League is number one in Europe at present.

"It has been obvious for three years that the Premier League has the upper hand," reflected Ferguson.

"But I am only happy for Manchester United because we had the hardest draw.

"We can play better than that and I am sure we will be better in the next round."

It was a disappointing night for Jose Mourinho, who after a lone walk to his dug-out before the teams had entered the field then suffered only his second defeat in 14 head-to-head confrontations with Ferguson.

He later came under verbal attack from the Italian journalists, who claimed he had only been hired to win the Champions League.

"They always like to find their own reasons for football things," scoffed Mourinho at his inquisitors.

"I prefer to analyse the situation. I can't speak for the past 50 years. I can only talk about the last four or five.

"The first thing I will do is have a meeting with my president to explain to him why we got knocked out and what we have to do. I am accountable to him. He is the person I need to speak to about how we reach the next stage.

"But there is not a psychological barrier. I am sad that we lost but there is no reason why we cannot go on to win the Scudetto (Serie A)."

Throughout the build-up and the matches themselves, Mourinho has given the impression of a man who would one day jump at the chance of replacing Ferguson.

For now he can only look on with envy as a United team at their peak carry all before them, the quintuple now just a 9-2 shot for the Premier League leaders, who tackle Liverpool at Old Trafford on Saturday.

"Manchester United have worked together for five consecutive years," said Mourinho.

"They were a young side then, they are not young anymore. Right now they are at their maximum level. That is why they are European champions. That is why they can win everything."