Man Utd boss Sir Alex Ferguson admits the quality of teams in the Champions League makes it increasingly difficult for Scottish clubs. While both halves of the Old Firm have reached the UEFA Cup final in recent times, only twice have they made the latter stages of Europe's number one club competition.
"Realistically, if you look at Celtic and Rangers, then consider there are four teams from Italy, Spain and England, it makes it difficult," said Ferguson.
"This season Juventus and Real Madrid are in a group, while Villarreal are in with us. Right at the very start did people honestly believe that Celtic would qualify? They were an outsider.
"Financially it is difficult but that doesn't mean it couldn't be done because Celtic's home record always gives them a big chance."