Sir Alex Ferguson insists he has learned the Champions League lessons of Copenhagen as United prepare to take on another unfancied Danish team in the shape of Aalborg BK.
Two years ago an under-strength Reds squad travelled to FC Copenhagen in control of Group F and needing only a point to qualify for the knockout stages.
But United put in a lacklustre performance to lose 1-0 and, after a further defeat to Celtic, were forced to beat Benfica in the final game to progress.
It's a situation Ferguson is determined to avoid this time around, and that means fielding his strongest team in the Energi Nord Arena on Tuesday.
"The most important thing is that Aalborg get our respect," the Reds boss told the pre-match press conference on Monday.
"They are a small club, with only 10,000 fans, but we must make sure we don’t fall into any traps and play to our best level.
"Two years ago we made a mistake in picking our team against Copenhagen because we were in a comfortable position in the group, and we ended up scrapping away for qualification, so we’ll definitely field our strongest team this time."
Aalborg claimed a creditable goalless draw away at Celtic in their opening Champions League game, and Ferguson admits he was impressed by the Danes' work ethic and compact gameplan which frustrated their Scottish opponents.
But the United manager warned that after an identical result against Villarreal at Old Trafford on Matchday 1, his side are much better prepared to claim a first win of their Champions League defence on Tuesday.
"Aalborg are a small club who have reached the Champions League, which is an enormous achievement in itself," Ferguson continued.