As United prepare to kick-off their European campaign against Benfica, THT looks back at the significance of this dual for the Red Devils. United have shared the best and the worst moments in Europe with the Portuguese giants. TheHardTackle looks back at 3 of the most important clashes between Man United and Benfica.

Some teams are remembered for their tactical innovations, like Rinuus Michel's Holland side or Arrigo Sacchi's Milan. Yet there are teams who, despite making important contributions to the game, have gone unnoticed. We take a look at five such teams.