Basel winger Xherdan Shaqiri claims Manchester United are paying the price for their own arrogance as the Red Devils gear up for a Europa League - not Champions League - tie on Thursday.
Shaqiri was a key figure in Basel's shock 2-1 victory over United at the back end of 2011, which signalled an end to their Champions League campaign. As a result, last year's finalists are now preparing for the second leg of a Europa League tie with Ajax in the round of 32.
Basel pulled off another upset by beating Bayern Munich 1-0 in the first leg of their Champions League last-16 tie on Wednesday, and Shaqiri - who joins Bayern in the summer - insisted United only had themselves to blame for their embarrassing defeat.
"United underestimated us. You could feel it in the tunnel and even in the warm-up," the 20-year-old said.
"They weren't fully focused and I'm not sure a United player made one sprint. Afterwards, you couldn't even swap shirts - they were gone that quickly."
Sir Alex Ferguson admits the lessons learned against Basel will stand United in good stead when they host Ajax at Old Trafford. The Red Devils lead 2-0, a similar advantage they held at home to Basel when they were pegged back to 3-3.
"You know the experience we had against Basel," Ferguson said. "We were 2-0 up at half-time and it stays in the memory bank, so I don't think we'll be casual or careless about what we're going to achieve here."