Victory over Barcelona would allow United to become the first side to win back-to-back European Cups since it was rebranded in 1992.

Liverpool and Nottingham Forest both achieved the feat in the 1970s. Now it is the Red Devils' turn to prove their worth if they win on Wednesday night.

"There have been a lot of unlucky teams in world football but when you look at the pantheon of great teams you need to have won the European Cup to have that tag," said Ferguson.

"There is no question about that. It has always been that way.

"Teams like Manchester United and Barcelona have to win the trophy to be regarded in that respect."

Victory for the 11-times Premier League champions would be a fourth success in Europe's most prestigious club competition, allowing them to draw level with Ajax and Bayern Munich, who both won the trophy on three successive occasions before the English began their dominance, and one behind Liverpool.

Ferguson cannot explain why those back-to-back triumphs have proved so elusive. He just knows the plaudits that await the team who finally does it.

"In the history of the European Cup it was done regularly," he observed.

"Some won it two or three times in a row. There were cycles of teams winning it like Ajax, Bayern and Real Madrid.

"Now we have an opportunity to change that and hopefully we can take it."