"It was a disappointing result and a disappointing performance," said Ferguson after yesterday's 1-0 defeat at home to Boro.
"We didn't deserve to win the match because we didn't create enough chances to win it and we have no excuses.
"I thought we would have galvanised ourselves in the second half but the tempo went up and we did our very best in terms of effort but we didn't have the quality to win it.
"We have come out of European ties in the past and performed very well, so that can't be an obvious reason we have to look at other things.
"We looked off the pace today. The club have risen to challenges in the past and now we have a big one. We need Liverpool and Arsenal to slip up."