Manchester United boss Sir Alex Ferguson admitted the passion of FA Cup opponents Crawley Town shocked his foreign players.
Gabriel Obertan and Bebe have drawn harsh criticism for their performances in the 1-0 win.
When asked what his players took from the tie, Fergie snapped: "Me losing my temper.
"We had some players who maybe don't understand what FA Cup football is like. For them, that is the biggest lesson.
"There is no doubt a few players did not do themselves justice. We weren't at the races in the second half, they made it very difficult for us in the second half and we were second to every ball."
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