Partizan Belgrade coach Savo Milosevic claimed on Wednesday that Manchester United are "definitely in the top three biggest clubs in the world even today."
United have struggled this season and have failed to win any of their last six matches in all competitions, a far cry from their all conquering days under the management of Sir Alex Ferguson.
Milosevic's side have an impressive home record in this competition and are unbeaten in Belgrade in Europe in their last 11 matches.
United for their part are undefeated home and away in 13 UEFA Europa League matches.
