[BBC]Aberdeen will contest the Scottish Cup final for only the third time this century andjust a fourth time since they last lifted the trophy in 1990.The fact the Dons had won the competition five times in the preceding nine seasons emphasises the issues they have had with the tournament since Brian Irvine beat Packie Bonner in the penalty shootout 35 years ago.The most important thing about semi-finals is winning them, performances are of secondary importance. However, the Dons laboured agains