the exeter players are still stupidly good don't forget. i played for a plymouth argyle youth side against an exeter team, including nigel mansells son and they whipped us, we were supposed to be the best in cornwall.many of them play now.
these two games are the reason why the fa cup is the best football competition in the world, minor teams can beat the huge teams purely because of the occasion.
they try alot harder and have nothing to lose, also man u are used to playing against other amazing sides where they are more organised so can put moves together, exeter are going nuts and closing down every ball not giving them any time and its alot scrappier than the prem so its a whole different situation for them.
if exeter where in the prem they would get a dicking every game without a doubt.